diff --git a/README.md b/README.md
index 1d088ef..feae690 100644
--- a/README.md
+++ b/README.md
@@ -2,9 +2,9 @@
 
 The material in this repository is divided by topic.  
 
-* Ruby
+* [Ruby](ruby/Open_Ruby_Overview.md)
 * SQL
-* Rails
+* [Rails](rails/Open_Rails_Overview.md)
 * HTML/CSS
 * JavaScript
 * React
diff --git a/rails/Open_Rails_Overview.md b/rails/Open_Rails_Overview.md
new file mode 100644
index 0000000..e6c6348
--- /dev/null
+++ b/rails/Open_Rails_Overview.md
@@ -0,0 +1,263 @@
+# Rails
+
+## Topics Covered
+
+- [Getting started](#getting-started)
+- [Routes and Controllers](#routes-and-controllers)
+- [Rails Views](#rails-views)
+- [Rails Auth](#rails-auth)
+- [Rails Auth II](#rails-auth-ii)
+- [Testing with Rails](#testing-with-rails)
+- [Rails and CSS](#rails-and-css)
+- [Advanced Rails Forms](#advanced-rails-forms)
+- [Rails Lite](#rails-lite)
+
+
+## Notes
+
+Rails is the third module in the App Academy Full Stack Developer Curriculum.
+
+As with all future modules, any "Bonus" projects are to be completed after the
+standard projects for each day are completed. Sometimes that could mean going
+back to previous day's "Bonus" projects if you otherwise finish early.
+Additional Resources are readings, videos, or articles that are not required,
+but will serve to deepen your understanding of a topic. They will be denoted
+with a specific icon in your task menu.
+
+### Getting started
+- [ ] 1. [Rails Setup](readings/rails-setup.md)
+- [ ] 2. [Rails API (api.rubyonrails.org)](http://api.rubyonrails.org/v5.1.3/)
+- [ ] 3. [Rails Guides (guides.rubyonrails.org)](http://guides.rubyonrails.org/v5.1.3/)
+- [ ] 4. [Diagram of Rails](https://assets.aaonline.io/fullstack/rails/assets/rails_diagram.png)
+- [ ] 5. [Rails 4 vs Rails 5](readings/rails-5-updates.md)
+### Routes and Controllers
+- [ ] 1. [What is an API?](https://player.vimeo.com/video/168498417)
+- [ ] 2. [HTTP Request/Response](https://player.vimeo.com/video/168498424)
+- [ ] 3. [Rails Routing](https://player.vimeo.com/video/168498679)
+- [ ] 4. [Routes Demo](https://player.vimeo.com/video/168499905)
+- [ ] 5. [Basic Controller Demo](https://player.vimeo.com/video/168501163)
+- [ ] 6. [RESTful Controller Demo](https://player.vimeo.com/video/168505535)
+- [ ] 7. [Routing I: Basics](readings/routing-part-i.md)
+- [ ] 8. [Basic Controllers and Strong Params](readings/basic-controllers.md)
+- [ ] 9. [Callbacks](readings/callbacks.md)
+- [ ] 10. [Delegation](readings/delegation.md)
+- [ ] 11. [Contextual Overview of DNS](readings/dns.md)
+- [ ] 12. [Testing Routes with Postman](readings/postman.md)
+- [ ] 13. [Routes and Controllers Quiz](quizzes/routes_and_controllers.md)
+- [ ] 14. [True Diversity is Intersectional](https://medium.com/projectinclude/true-diversity-is-intersectional-2282b8da8882)
+- [ ] 15. [6-Year-Old Girls Already Have Gendered Beliefs About Intelligence](https://www.theatlantic.com/science/archive/2017/01/six-year-old-girls-already-have-gendered-beliefs-about-intelligence/514340/)
+- [ ] 16. [VCs and Female Entrepreneurs](https://hbr.org/2017/05/we-recorded-vcs-conversations-and-analyzed-how-differently-they-talk-about-female-entrepreneurs)
+- [ ] 17. [Elephant in the Valley](https://www.elephantinthevalley.com/)
+- [ ] 18. [When Bias in Product Design Means Life or Death](https://techcrunch.com/2016/11/16/when-bias-in-product-design-means-life-or-death/)
+- [ ] 19. [Basic JSON API](readings/basic-json-api.md)
+- [ ] 20. [Routing II: Nested Collections](readings/routing-part-ii.md)
+- [ ] 21. [Routing III: Adding non-default routes](readings/routing-part-iii.md)
+- [ ] 22. [(cc) 03-basic-rails-routing](https://player.vimeo.com/video/100267303)
+- [ ] 23. [(cc) 04-strong-params](https://player.vimeo.com/video/100267304)
+- [ ] 24. [(cc) 05-nested-resources](https://player.vimeo.com/video/100267305)
+- [ ] 25. [(cc) 06-erb-and-views](https://player.vimeo.com/video/100267306)
+- [ ] 26. [(cc) 07-basic-forms](https://player.vimeo.com/video/100358537)
+- [ ] 27. [(cc) 08-form-request-cycle](https://player.vimeo.com/video/100359278)
+- [ ] 28. [(cc) 09-select](https://player.vimeo.com/video/100729432)
+- [ ] 29. [(cc) 10-form-partial](https://player.vimeo.com/video/100729434)
+- [ ] 30. [(cc) 11-form-encoding](https://player.vimeo.com/video/100729434)
+- [ ] 31. [Code from Rails demos (Intro Rails Video Demo)](https://assets.aaonline.io/fullstack/rails/demos/intro_rails_video_demo.zip)
+- [ ] 32. [Rails Routing Intro](https://player.vimeo.com/video/335016614)
+- [ ] 33. [First Route & Controller Action](https://player.vimeo.com/video/335017586)
+- [ ] 34. [Show Controller Action](https://player.vimeo.com/video/335018812)
+- [ ] 35. [Create & New Controller Actions](https://player.vimeo.com/video/335019368)
+- [ ] 36. [Update & Destroy Controller Actions](https://player.vimeo.com/video/335021237)
+- [ ] 37. [First Routes and Controllers](projects/first_routes/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/first_routes/solution.zip)
+- [ ] 38. [Art Share API](projects/art_share_api/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/art_share_api/solution.zip)
+- [ ] 39. [CSS Friends Part 1](../html-css/micro-projects/css_friends_combined/css_friends_0/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/html-css/micro-projects/combined-css-friends/css-friends-pt1/solution.zip)
+- [ ] 40. [Art Share API (Part Two)](projects/art_share_api/README_part_two.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/art_share_api/solution.zip)
+- [ ] 41. [Art Share API Solutions](https://player.vimeo.com/video/335906952)
+
+### Rails Views
+- [ ] 1. [Rails Views: Intro](https://player.vimeo.com/video/194372657)
+- [ ] 2. [Rails Views: Forms](https://player.vimeo.com/video/194376967)
+- [ ] 3. [Rails Views: Partials](https://player.vimeo.com/video/194385069)
+- [ ] 4. [Debugging a Rails Project](https://player.vimeo.com/video/194394048)
+- [ ] 5. [Code from Rails demos (Library Demo)](https://assets.aaonline.io/fullstack/rails/demos/library_demo.zip)
+- [ ] 6. [Rails Views Quiz](quizzes/views.md)
+- [ ] 7. [Partials](readings/partials.md)
+- [ ] 8. [ERB](readings/erb.md)
+- [ ] 9. [Rails Parameter Conventions](readings/parameter-conventions.md)
+- [ ] 10. [Debugging](readings/debugging-rails.md)
+- [ ] 11. [Easy Forms Demo](https://assets.aaonline.io/fullstack/rails/demos/easy_forms_demo.zip)
+- [ ] 12. [Ternary Logic in SQL](../sql/readings/sql-ternary-logic.md)
+- [ ] 13. [Rails Views - BleatsController#index](https://player.vimeo.com/video/335909324)
+- [ ] 14. [Rails Views - BleatsController#show](https://player.vimeo.com/video/335911420)
+- [ ] 15. [Rails Views - BleatsController#new & #create](https://player.vimeo.com/video/335912633)
+- [ ] 16. [Rails Views - BleatsController#edit & #update](https://player.vimeo.com/video/335917285)
+- [ ] 17. [Partials Lecture](https://player.vimeo.com/video/335919026)
+- [ ] 18. [Rails Views - BleatsController#destroy](https://player.vimeo.com/video/335920703)
+- [ ] 19. [99 Cats](projects/ninety_nine_cats_i/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/ninety_nine_cats_i/solution.zip)
+### Rails Auth
+- [ ] 1. [Secure State](https://player.vimeo.com/video/160819941)
+- [ ] 2. [Cookies and Authentication](https://player.vimeo.com/video/160820294)
+- [ ] 3. [Encoding and Encryption](https://player.vimeo.com/video/160820971)
+- [ ] 4. [Hashing for Authentication](https://player.vimeo.com/video/160821222)
+- [ ] 5. [Salting](https://player.vimeo.com/video/160822597)
+- [ ] 6. [BCrypt](https://player.vimeo.com/video/160825250)
+- [ ] 7. [Session and Flash](https://player.vimeo.com/video/160824886)
+- [ ] 8. [Auth Pattern](https://player.vimeo.com/video/160826910)
+- [ ] 9. [(cc) 06 CSRF Attack](https://player.vimeo.com/video/93114286)
+- [ ] 10. [(cc) 07 CSRF Protection](https://player.vimeo.com/video/93114288)
+- [ ] 11. [(cc) 08 CSRF Methods](https://player.vimeo.com/video/93114287)
+- [ ] 12. [Singular resource](readings/singular-resources.md)
+- [ ] 13. [Rails Auth Quiz](quizzes/auth.md)
+- [ ] 14. [Cookies, JSON](https://player.vimeo.com/video/336447623)
+- [ ] 15. [Encrypted Cookies & #session](https://player.vimeo.com/video/336448651)
+- [ ] 16. [#flash & #flash.now](https://player.vimeo.com/video/336449027)
+- [ ] 17. [Rails Auth](homeworks/rails-auth/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/homeworks/rails-auth/solution.zip)
+- [ ] 18. [Cookies](readings/cookies.md)
+- [ ] 19. [Controllers and State](readings/controllers-and-state.md)
+- [ ] 20. [CSRF and Forms](readings/csrf.md)
+- [ ] 21. [Displaying validation errors; flash](readings/validation.md)
+- [ ] 22. [Auth I: Creating Users](demos/rails-auth/README.md)
+- [ ] 23. [Auth II: Sessions](demos/rails-auth/README-Part-II.md)
+- [ ] 24. [Common User Auth Questions](readings/common_auth_questions.md)
+- [ ] 25. [99Cats pt. 1 Solution](https://player.vimeo.com/video/336446896)
+- [ ] 26. [User Password Functionality & User Signup](https://player.vimeo.com/video/336449760)
+- [ ] 27. [Auth Intro, Log In on Signup, #current_user](https://player.vimeo.com/video/336451736)
+- [ ] 28. [SessionsController](https://player.vimeo.com/video/336452376)
+- [ ] 29. [Authorization (before_action)](https://player.vimeo.com/video/336453330)
+- [ ] 30. [99 Cats II: Auth](projects/ninety_nine_cats_ii/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/ninety_nine_cats_ii/solution.zip)
+### Rails Auth II
+- [ ] 1. [(cc) 14-radio-and-textarea](https://player.vimeo.com/video/100729825)
+- [ ] 2. [(cc) 15-helpers](https://player.vimeo.com/video/100780885)
+- [ ] 3. [layouts](https://player.vimeo.com/video/168822741)
+- [ ] 4. [ActionMailer](readings/mailer.md)
+- [ ] 5. [View helpers](readings/helpers.md)
+- [ ] 6. [View layouts](readings/layouts.md)
+- [ ] 7. [Nontechnical Overview of Rails](readings/rails_nontech.md)
+- [ ] 8. [Helpers, Layouts, and Partials](homeworks/helpers-layouts-mailer/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/homeworks/helpers-layouts-mailer/solution.zip)
+- [ ] 9. [Action Mailer Demo](https://player.vimeo.com/video/168810895)
+- [ ] 10. [CSRF Attacks & Protection](https://player.vimeo.com/video/336454209)
+- [ ] 11. [Auth Review](https://player.vimeo.com/video/336455270)
+- [ ] 12. [Music App](projects/music_app/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/music_app/solution.zip)
+- [ ] 13. [Helpers Layouts Mailers](projects/helpers_layouts_mailers/README.md)
+
+### Testing with Rails
+- [ ] 1. [Rails Testing: Intro](https://player.vimeo.com/video/292415799)
+- [ ] 2. [Rails Testing: Setup](https://player.vimeo.com/video/292423696)
+- [ ] 3. [Rails Testing: Models](https://player.vimeo.com/video/292829125)
+- [ ] 4. [Rails Testing: Factories](https://player.vimeo.com/video/292829352)
+- [ ] 5. [Rails Testing: Controllers](https://player.vimeo.com/video/292827733)
+- [ ] 6. [Rails Testing: Capybara](https://player.vimeo.com/video/292828799)
+- [ ] 7. [Code from Rails Testing demo (Capybara Party](https://assets.aaonline.io/fullstack/rails/demos/CapybaraParty.zip)
+- [ ] 8. [RSpec View Testing](readings/rspec-views.md)
+- [ ] 9. [Capybara](homeworks/capybara/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/homeworks/capybara/solution.md)
+- [ ] 10. [Integration Testing](readings/integration-testing.md)
+- [ ] 11. [RSpec and Rails Setup](readings/rspec-and-rails-setup.md)
+- [ ] 12. [Testing Models](readings/rspec-models.md)
+- [ ] 13. [FactoryBot and Faker Gems](readings/factorybot-and-faker.md)
+- [ ] 14. [Testing Controllers](readings/rspec-controllers.md)
+- [ ] 15. [Testing with Capybara](readings/capybara.md)
+- [ ] 16. [Spring and Guard Setup](readings/guard-spring-setup.md)
+- [ ] 17. [Shoulda Matchers Setup](readings/shoulda-matchers-setup.md)
+- [ ] 18. [Rails Testing Intro & Model Tests](https://player.vimeo.com/video/336465423)
+- [ ] 19. [Rails Controller Testing](https://player.vimeo.com/video/336466846)
+- [ ] 20. [Rails Feature Tests](https://player.vimeo.com/video/336467425)
+- [ ] 21. [Goal App](projects/goal_app/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/goal_app/solution.zip)
+- [ ] 22. [Appacademy.io Tests (Bonus)](projects/appacademy.io_tests/README.md)
+### Rails and CSS
+- [ ] 1. [CSS Nontechnical Overview](../html-css/readings/css_nontech.md)
+- [ ] 2. [CSS Responsive Design](../html-css/readings/responsive_design.md)
+- [ ] 3. [CSS Quiz](quizzes/css.md)
+- [ ] 4. [Positioning & Media Queries](../html-css/micro-projects/positioning_media_queries/exercise.md)
+  - [Solution](https://assets.aaonline.io/fullstack/html-css/micro-projects/positioning_media_queries/solution.zip)
+- [ ] 5. [CSS Review](../html-css/projects/css_review/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/html-css/projects/css_review/solution.zip)
+- [ ] 6. [CSS Review Video](https://player.vimeo.com/video/214597789)
+- [ ] 7. [CSS Intro](../html-css/lecture_readings/intro_to_css.md)
+- [ ] 8. [CSS Syntax](../html-css/lecture_readings/css_syntax.md)
+- [ ] 9. [CSS Display](../html-css/lecture_readings/css_display.md)
+- [ ] 10. [CSS Box Model](../html-css/lecture_readings/css_box_model.md)
+- [ ] 11. [CSS Margin](../html-css/lecture_readings/css_margin.md)
+- [ ] 12. [CSS Inheritence](../html-css/lecture_readings/css_inherit.md)
+- [ ] 13. [CSS Reset](../html-css/lecture_readings/css_reset.md)
+- [ ] 14. [CSS Pseudo Content](../html-css/lecture_readings/css_pseudo_content.md)
+- [ ] 15. [CSS Float](../html-css/lecture_readings/css_float.md)
+- [ ] 16. [CSS Grid](../html-css/lecture_readings/css_grid.md)
+- [ ] 17. [CSS Navbar Demo](../html-css/lecture_readings/css_navbar.md)
+- [ ] 18. [CSS Positioning](../html-css/lecture_readings/css_positioning.md)
+- [ ] 19. [CSS Glasses Demo](../html-css/lecture_readings/css_glasses.md)
+- [ ] 20. [CSS Transform Property](http://css-tricks.com/almanac/properties/t/transform/)
+- [ ] 21. [Flexbox Froggy](https://flexboxfroggy.com/)
+- [ ] 22. [Flexbox Defense](http://www.flexboxdefense.com/)
+- [ ] 23. [CSS Grid Garden](http://cssgridgarden.com/)
+- [ ] 24. [Intro & Boxes Demo](https://player.vimeo.com/video/337140888)
+- [ ] 25. [Display Property & Floats Demo](https://player.vimeo.com/video/337142705)
+- [ ] 26. [Flexbox Demo](https://player.vimeo.com/video/337144348)
+- [ ] 27. [Position Demo](https://player.vimeo.com/video/337146602)
+- [ ] 28. [Styling Demo with Rails](https://player.vimeo.com/video/337149109)
+- [ ] 29. [AA Times](../html-css/projects/aa_times/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/html-css/projects/aa_times/solution.zip)
+- [ ] 30. [AA Times (Part Two)](../html-css/projects/aa_times/part_two.md)
+  - [Solution](https://assets.aaonline.io/fullstack/html-css/projects/aa_times/solution.zip)
+- [ ] 31. [Google Homepage (Bonus)](../html-css/projects/google_homepage/README.md)
+  - [Solution](https://www.google.com/)
+- [ ] 32. [Have You Experienced Racism in the Workplace?](https://www.comparably.com/guest/culture/tech/all-departments/109-have-you-ever-experienced-racism-in-the-workplac)
+- [ ] 33. [Diversity in Tech Remains Elusive](https://modelviewculture.com/pieces/diversity-in-tech-remains-elusive-due-to-racism-lack-of-representation-and-cultural-differences)
+- [ ] 34. [Commoditization and Exploitation of Asians in Tech](https://modelviewculture.com/pieces/damaged-karma-commoditization-and-exploitation-of-asians-in-tech)
+- [ ] 35. [The Other Side of Diversity](https://medium.com/this-is-hard/the-other-side-of-diversity-1bb3de2f053e)
+- [ ] 36. [How AI is Learning All of Our Worst Impulses](https://www.theguardian.com/inequality/2017/aug/08/rise-of-the-racist-robots-how-ai-is-learning-all-our-worst-impulses)
+### Advanced Rails Forms
+- [ ] 1. [(cc) 16-tag-ids-setter](https://player.vimeo.com/video/100780886)
+- [ ] 2. [(cc) 17-checkboxes-1](https://player.vimeo.com/video/100780887)
+- [ ] 3. [(cc) 18-checkboxes-2](https://player.vimeo.com/video/100846847)
+- [ ] 4. [(cc) 19-checkboxes-3](https://player.vimeo.com/video/100846848)
+- [ ] 5. [(cc) 20-query-string](https://player.vimeo.com/video/100849678)
+- [ ] 6. [Polymorphic Associations: Section 2.9](http://guides.rubyonrails.org/association_basics.html#polymorphic-associations)
+- [ ] 7. [Rails Forms Quiz](quizzes/rails_forms.md)
+- [ ] 8. [Polymorphism and Concerns](homeworks/polymorphism-concerns/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/homeworks/polymorphism-concerns/solution.zip)
+- [ ] 9. [Decorators (Bonus)](readings/decorators.md)
+- [ ] 10. [Checkboxes and Id Setters Reference](readings/checkboxes.md)
+- [ ] 11. [RedditClone](projects/reddit_on_rails/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/reddit_on_rails/solution.zip)
+- [ ] 12. [Goal App Refactor](projects/goal_app_refactor/README.md)
+### Rails Lite
+- [ ] 1. [Rails Lite Intro](https://player.vimeo.com/video/161381457)
+- [ ] 2. [HTTP](https://player.vimeo.com/video/161381484)
+- [ ] 3. [HTTP Demo](https://player.vimeo.com/video/161381489)
+- [ ] 4. [Rails from the Inside Out](https://player.vimeo.com/video/161381601)
+- [ ] 5. [Rack](https://player.vimeo.com/video/161384649)
+- [ ] 6. [Rack Demo](https://player.vimeo.com/video/161381828)
+- [ ] 7. [Contextual Overview of TCP/IP](readings/tcp_ip.md)
+- [ ] 8. [RegexOne](http://regexone.com/)
+- [ ] 9. [RegexOne (Lesson 1 - 6)](https://regexone.com/lesson/repeating_characters)
+- [ ] 10. [RegexOne (Lesson 7 - 14)](https://regexone.com/lesson/kleene_operators)
+- [ ] 11. [Rails Lite Quiz](quizzes/rails_lite.md)
+- [ ] 12. [Rack Middleware](https://player.vimeo.com/video/161382367)
+- [ ] 13. [Rack Middleware Demo](https://player.vimeo.com/video/161386029)
+- [ ] 14. [Rack Middleware Demo code](https://assets.aaonline.io/fullstack/rails/demos/middleware.rb)
+- [ ] 15. [TCP](https://player.vimeo.com/video/161382361)
+- [ ] 16. [DNS](https://player.vimeo.com/video/161381921)
+- [ ] 17. [(cc) 00-webserver](https://player.vimeo.com/video/100169899)
+- [ ] 18. [(cc) 01-protocols](https://player.vimeo.com/video/100169898)
+- [ ] 19. [(cc) 02-http](https://player.vimeo.com/video/100267302)
+- [ ] 20. [HTTP Reading](readings/http.md)
+- [ ] 21. [Rack Reading](readings/rack.md)
+- [ ] 22. [Rack Middleware Stack](readings/middleware.md)
+- [ ] 23. [Class and Instance Eval](readings/instance-eval-class-eval.md)
+- [ ] 24. [Rack - Intro & Basic Apps](https://player.vimeo.com/video/337172677)
+- [ ] 25. [Rack - Request & Response](https://player.vimeo.com/video/337173410)
+- [ ] 26. [Rack - Class App](https://player.vimeo.com/video/337174410)
+- [ ] 27. [Rails Lite Part 1](projects/rails_lite/rails-lite-i.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/rails_lite/solution.zip)
+- [ ] 28. [Rails Lite Part 2](projects/rails_lite/rails-lite-ii.md)
+  - [Solution](https://assets.aaonline.io/fullstack/rails/projects/rails_lite/solution.zip)
diff --git a/rails/demos/rails-auth/.gitattributes b/rails/demos/rails-auth/.gitattributes
new file mode 100644
index 0000000..34fb547
--- /dev/null
+++ b/rails/demos/rails-auth/.gitattributes
@@ -0,0 +1,7 @@
+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
\ No newline at end of file
diff --git a/rails/demos/rails-auth/.gitignore b/rails/demos/rails-auth/.gitignore
new file mode 100644
index 0000000..4f0da6f
--- /dev/null
+++ b/rails/demos/rails-auth/.gitignore
@@ -0,0 +1,26 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
\ No newline at end of file
diff --git a/rails/demos/rails-auth/.ruby-version b/rails/demos/rails-auth/.ruby-version
new file mode 100644
index 0000000..94ff29c
--- /dev/null
+++ b/rails/demos/rails-auth/.ruby-version
@@ -0,0 +1 @@
+3.1.1
diff --git a/rails/demos/rails-auth/Gemfile b/rails/demos/rails-auth/Gemfile
new file mode 100644
index 0000000..cea6ef9
--- /dev/null
+++ b/rails/demos/rails-auth/Gemfile
@@ -0,0 +1,35 @@
+source "https://rubygems.org"
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+ruby "3.1.1"
+
+# Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
+gem "rails", "~> 7.0.3"
+
+# The original asset pipeline for Rails [https://github.com/rails/sprockets-rails]
+gem "sprockets-rails"
+
+# Use postgresql as the database for Active Record
+gem "pg", "~> 1.1"
+
+# Use the Puma web server [https://github.com/puma/puma]
+gem "puma", "~> 5.0"
+
+# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
+gem "tzinfo-data", platforms: %i[ mingw mswin x64_mingw jruby ]
+
+gem "bcrypt"
+
+group :development, :test do
+  # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
+  gem "byebug", platforms: %i[ mri mingw x64_mingw ]
+end
+
+group :development do
+  # Speed up commands on slow machines / big apps [https://github.com/rails/spring]
+  # gem "spring"
+  gem "annotate"
+  gem "pry-rails"
+  gem "better_errors"
+  gem "binding_of_caller"
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/Gemfile.lock b/rails/demos/rails-auth/Gemfile.lock
new file mode 100644
index 0000000..6e940be
--- /dev/null
+++ b/rails/demos/rails-auth/Gemfile.lock
@@ -0,0 +1,193 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailbox (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (>= 2.7.1)
+      net-imap
+      net-pop
+      net-smtp
+    actionmailer (7.0.3)
+      actionpack (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (~> 2.5, >= 2.5.4)
+      net-imap
+      net-pop
+      net-smtp
+      rails-dom-testing (~> 2.0)
+    actionpack (7.0.3)
+      actionview (= 7.0.3)
+      activesupport (= 7.0.3)
+      rack (~> 2.0, >= 2.2.0)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (7.0.3)
+      actionpack (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.6.0)
+      nokogiri (>= 1.8.5)
+    actionview (7.0.3)
+      activesupport (= 7.0.3)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.3.6)
+    activemodel (7.0.3)
+      activesupport (= 7.0.3)
+    activerecord (7.0.3)
+      activemodel (= 7.0.3)
+      activesupport (= 7.0.3)
+    activestorage (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activesupport (= 7.0.3)
+      marcel (~> 1.0)
+      mini_mime (>= 1.1.0)
+    activesupport (7.0.3)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+    annotate (3.2.0)
+      activerecord (>= 3.2, < 8.0)
+      rake (>= 10.4, < 14.0)
+    bcrypt (3.1.18)
+    better_errors (2.9.1)
+      coderay (>= 1.0.0)
+      erubi (>= 1.0.0)
+      rack (>= 0.9.0)
+    binding_of_caller (1.0.0)
+      debug_inspector (>= 0.0.1)
+    builder (3.2.4)
+    byebug (11.1.3)
+    coderay (1.1.3)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    debug_inspector (1.1.0)
+    digest (3.1.0)
+    erubi (1.10.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
+      concurrent-ruby (~> 1.0)
+    loofah (2.18.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (1.0.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    minitest (5.15.0)
+    net-imap (0.2.3)
+      digest
+      net-protocol
+      strscan
+    net-pop (0.1.1)
+      digest
+      net-protocol
+      timeout
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    pg (1.3.5)
+    pry (0.14.1)
+      coderay (~> 1.1)
+      method_source (~> 1.0)
+    pry-rails (0.3.9)
+      pry (>= 0.10.4)
+    puma (5.6.4)
+      nio4r (~> 2.0)
+    racc (1.6.0)
+    rack (2.2.3.1)
+    rack-test (1.1.0)
+      rack (>= 1.0, < 3)
+    rails (7.0.3)
+      actioncable (= 7.0.3)
+      actionmailbox (= 7.0.3)
+      actionmailer (= 7.0.3)
+      actionpack (= 7.0.3)
+      actiontext (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activemodel (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      bundler (>= 1.15.0)
+      railties (= 7.0.3)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.4.2)
+      loofah (~> 2.3)
+    railties (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      method_source
+      rake (>= 12.2)
+      thor (~> 1.0)
+      zeitwerk (~> 2.5)
+    rake (13.0.6)
+    sprockets (4.0.3)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.4.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      sprockets (>= 3.0.0)
+    strscan (3.0.3)
+    thor (1.2.1)
+    timeout (0.3.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    websocket-driver (0.7.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
+    zeitwerk (2.5.4)
+
+PLATFORMS
+  x86_64-darwin-20
+
+DEPENDENCIES
+  annotate
+  bcrypt
+  better_errors
+  binding_of_caller
+  byebug
+  pg (~> 1.1)
+  pry-rails
+  puma (~> 5.0)
+  rails (~> 7.0.3)
+  sprockets-rails
+  tzinfo-data
+
+RUBY VERSION
+   ruby 3.1.1p18
+
+BUNDLED WITH
+   2.3.14
diff --git a/rails/demos/rails-auth/README-Part-II.md b/rails/demos/rails-auth/README-Part-II.md
new file mode 100644
index 0000000..6a895ac
--- /dev/null
+++ b/rails/demos/rails-auth/README-Part-II.md
@@ -0,0 +1,368 @@
+# Authentication II: Creating a Session
+
+The Auth Demo project shows you how to set up basic authentication for your
+Rails apps. The previous reading, Part I, covers the creation of users. This
+reading, Part II, covers the creation of a session. Feel free to code along. To
+download the full solution for this demo, see Part I.
+
+Here is a visualization of the login process.
+![Login](https://assets.aaonline.io/fullstack/rails/assets/login_diagram.png)
+
+## Overview
+
+You are now successfully creating users. Now you just need to let them log in!
+
+You're going to create a (singular) resource named `session`. When a user logs
+in, they'll go to `/session/new` to fill in their credentials. `POST`ing to
+`/session` (i.e., to the `SessionsController#create` action) will sign the user
+in; you'll store a _session token_ in the cookie so that subsequent requests
+will know which user is logged in. Lastly, to log out, the client can issue a
+`DELETE` request to `/session`.
+
+A couple notes:
+
+* There is no `Session` model class, nor a `sessions` table. You can still
+  create a `session` resource, however: a `session` resource just requires that
+  you have a `SessionsController` (see below).
+* The `session` resource is **singular** because the user will use at
+  most one session: their own.
+* You'll write a `SessionsController`; even when using a singular
+  resource, controllers are **always** pluralized.
+
+## Phase IV: Logging in: Verifying credentials
+
+On to implementation!
+
+### Adding a `session` resource, `SessionsController`
+
+First, add a `session` resource to the routes file and generate a
+`SessionsController`.
+
+Next, write a `new` form that allows a user to submit their username and
+password. Take advantage of the shared form that you created in Part I:
+
+```erb
+<!-- app/views/sessions/new.html.erb -->
+
+<h1>Log in!</h1>
+
+<%= render "shared/form", task: "login" %>
+```
+
+Okay, but what about the `create` action?
+
+### Adding `::find_by_credentials`
+
+You need to write `SessionsController#create` so that it verifies the
+username/password and then sets a session token.
+
+To verify the username and password, add a `find_by_credentials` method to your
+`User` model:
+
+```ruby
+class User < ApplicationRecord
+  # ...
+
+  def self.find_by_credentials(username, password)
+    user = User.find_by(username: username)
+    return nil if user.nil?
+    user.is_password?(password) ? user : nil
+  end
+
+  # ...
+end
+```
+
+This will return a user only if the username and password are correct.
+
+In your controller, add the following definitions for the `create` and `new`
+actions:
+
+```ruby
+class SessionsController < ApplicationController
+  def create
+    user = User.find_by_credentials(
+      params[:user][:username],
+      params[:user][:password]
+    )
+
+    if user.nil?
+      render json: "Invalid credentials".to_json
+    else
+      render json: "Welcome back #{user.username}!".to_json
+    end
+  end
+
+  def new
+  end
+end
+```
+
+> **Note:** While it is true that `render json:` normally calls `to_json` on any
+> non-JSON-ified object, you have to call it explicitly for strings. Why?
+> Because JSON essentially is a string, Rails assumes that any string passed to
+> `render json:` is already a JSON-ified string.
+
+Cool! But this is useless, because the sessions controller currently doesn't set
+a cookie to remember the logged-in user.
+
+## Phase V: Logging in: Setting the session token
+
+You now have the `SessionsController` properly verifying a user's credentials,
+but it doesn't actually do anything with the successful login. Let's fix that.
+
+### Add a `UsersController#show` page
+
+Make a very simple `show` view for your `UsersController`.
+
+```erb
+<!-- app/views/users/show.html.erb -->
+<h1><%= @user.username %></h1>
+
+<p>Hello, dear user!</p>
+```
+
+Edit the `create` method in `UsersController` and `SessionsController` to
+redirect to this page on successful form submission.
+
+Let's make the show page private: a user should be the only one allowed to look
+at their own `users#show` page. To enable this functionality, you need to know
+which user is logged in and trying to view the page. To know which user is
+logged in, you need to set a session token...
+
+### Adding `session_token` to `user`
+
+You need to introduce a `session_token` so that after login you can remember the
+current user. Begin by writing a migration:
+
+```ruby
+class AddSessionTokenToUsers < ActiveRecord::Migration[7.0]
+  def change
+    add_column :users, :session_token, :string, null: false
+    add_index :users, :session_token, unique: true
+  end
+end
+```
+
+Next, make sure that when you create a `User` it has a unique `session_token`:
+
+```ruby
+class User < ApplicationRecord
+  # ...
+
+  validates :session_token, presence: true, uniqueness: true
+  before_validation :ensure_session_token
+
+  # ...
+
+  def reset_session_token!
+    self.session_token = generate_unique_session_token
+    self.save!
+    self.session_token
+  end
+
+  private
+
+  def generate_unique_session_token
+    # `SecureRandom::urlsafe_base64` does not guarantee uniqueness. Wrapping
+    # this call in a loop ensures that no other user has the generated token.
+    loop do
+      session_token = SecureRandom::urlsafe_base64(16)
+      return session_token unless User.exists?(session_token: session_token)
+    end
+  end
+
+  def ensure_session_token
+    self.session_token ||= generate_unique_session_token
+  end
+end
+```
+
+`User` now validates the presence (and uniqueness) of the `session_token`. Note,
+though, that if a `User` instance does not already have a `session_token`, this
+code will conveniently generate a session token before the validations
+run; that's the `before_validation` callback bit. In other words, this presence
+validation should never fail.
+
+> Note: You can achieve a similar effect by using an `after_initialize
+> :ensure_session_token` callback instead of the `before_validation`.
+> `after_initialize`, however, will run every time a `User` instance is created,
+> **including whenever you find a user in the database!** `before_validation`,
+> in contrast, runs **before every validation**, which is when you actually need
+> to make sure you have a `session_token`.
+
+### Setting The Session
+
+You're now storing the session token in the `User` instance, but you also need
+to store it in the `session`. Write some helper methods in the
+`ApplicationController` to take care of this:
+
+```ruby
+class ApplicationController < ActionController::Base
+  def login!(user)
+    @current_user = user
+    session[:session_token] = user.session_token
+  end
+
+  def current_user
+    return nil if session[:session_token].nil?
+    @current_user ||= User.find_by(session_token: session[:session_token])
+  end
+end
+```
+
+To enable your views to access this `current_user` method, use `helper_method`:
+
+```ruby
+class ApplicationController < ActionController::Base
+  helper_method :current_user
+  # ...
+end
+```
+
+This will make `current_user` available in all views.
+
+Finally, update your `SessionsController` and `UsersController` `create`
+methods:
+
+```ruby
+class SessionsController < ApplicationController
+  def create
+    user = User.find_by_credentials(
+      params[:user][:username],
+      params[:user][:password]
+    )
+
+    if user.nil?
+      render json: "Invalid credentials".to_json
+    else
+      login!(user)
+      redirect_to user_url(user)
+    end
+  end
+
+  # ...
+end
+
+class UsersController < ApplicationController
+  def create
+    @user = User.new(user_params)
+
+    if @user.save
+      login!(@user)
+      redirect_to user_url(@user)
+    else
+      render json: @user.errors.full_messages
+    end
+  end
+
+  # ...
+end
+```
+
+## Phase VI: Adding a `Logout` button
+
+You haven't written any logout functionality, nor do you ever tell the user who
+they are logged in as. Fix that by editing the application's layout:
+
+```erb
+<!-- app/views/layouts/application.html.erb -->
+
+<html>
+<!-- ... -->
+  <body>
+
+    <% if !current_user.nil? %>
+      <ul>
+        <li>Logged in as: <%= current_user.username %></li>
+        <li>
+          <form action="<%= session_url %>" method="POST">
+            <input type="hidden"
+                   name="authenticity_token"
+                   value="<%= form_authenticity_token %>">
+            <input type="hidden" value="delete" name="_method" />
+            <input type="submit" value="Logout" />
+          </form>
+        </li>
+      </ul>
+    <% end %>
+
+    <%= yield %>
+  </body>
+</html>
+```
+
+Now, after you log in, you should be able to see the `Logout` button. But
+you don't have a destroy action yet. Go ahead and write one:
+
+```ruby
+class ApplicationController < ActionController::Base
+  # ...
+
+  def logout!
+    current_user.try(:reset_session_token!)
+    session[:session_token] = nil
+  end
+end
+
+class SessionsController < ApplicationController
+  # ...
+
+  def destroy
+    logout!
+    redirect_to new_session_url
+  end
+
+  # ...
+end
+```
+
+Now sign out should be working. Notice that in `logout!`
+you reset the session token. This will invalidate the old session
+token. You want to do that in case anyone has managed to steal the
+token; this will deny the thieves further access to the account.
+
+### Adding a `before_action` callback
+
+Finally, go ahead and finish what you started: protect the `users#show`
+page so that only the user themselves can view their own `show` page.
+
+To do that, write a `require_current_user!` helper:
+
+```ruby
+class ApplicationController < ActionController::Base
+  # ...
+
+  def require_current_user!
+    redirect_to new_session_url if current_user.nil?
+  end
+end
+```
+
+You can then add this as a `before_action` callback in your `UsersController`:
+
+```ruby
+class UsersController < ApplicationController
+  before_action :require_current_user!, except: %i(create new)
+
+  # ...
+end
+```
+
+By default, a `before_action` callback will run the specified method--here,
+`require_current_user!`--before running any of the actions in the file. Note,
+however, that the `create` and `new` actions are excepted in the code above:
+those actions are needed before a user signs up, so there's no way for the user
+to be logged in at that point.
+
+A rule of `before_action` is that, if running the filter causes a `redirect_to`,
+the action method will not be called. For instance, if a user tries to visit the
+`users#show` page without having logged in first, the callback will issue a
+redirect, and Rails will forgo calling the `UsersController#show` method.
+
+### Wait just one second...
+
+The callback you defined requires that a user be logged in to look at a
+`users#show` page. It does not, however, enforce that user A may not look at
+user B's show page. Write a new `before_action` filter in the `UsersController`
+to do this.
\ No newline at end of file
diff --git a/rails/demos/rails-auth/README.md b/rails/demos/rails-auth/README.md
new file mode 100644
index 0000000..bc574fe
--- /dev/null
+++ b/rails/demos/rails-auth/README.md
@@ -0,0 +1,390 @@
+# Authentication I: Creating Users
+
+The Auth Demo project shows you how to set up basic authentication for your
+Rails apps. This reading, Part I, covers the creation of users. The next
+reading, Part II, covers the creation of a session. Feel free to code along. You
+can also download the full solution for this demo at the `Download Project`
+button below.
+
+Here is a diagram of what signing up a user looks like.
+![Sign Up Diagram][sign-up-diagram]
+
+## Phase I: BCrypt
+
+### Don't store passwords in the database
+
+**Never store passwords in the database.** Storing passwords is bad because if
+someone hacks your server and gains access to the database, they will be able to
+steal all of your users' passwords. Since your users probably use the same
+password across multiple services, the hacker will likely be able to log in to a
+user's Gmail, Facebook, etc.
+
+### What is a hash function?
+
+The solution to this problem is to use a **hash function**. A hash function is a
+"one-way" function; it is easy to compute in one direction, but difficult to
+revert. Meaning that given a password, you can easily calculate the hash value
+of the password, but there is no easy way to go back and recover the password
+from the hash.
+
+Basically, a hash is sort of like scrambling an egg: scrambling is easy,
+unscrambling, not so much. The fancy mathematical trick--leave this step to
+the mathematicians!--is to design a function where:
+
+* You scramble things the same way every time: the same password will hash to
+  the same value every time.
+* That means the scrambling isn't really random; if the scrambling were totally
+  random, you'd calculate a new, different hash every time.
+* Even though the scrambling isn't truly random, it should still be difficult
+  (that is, near impossible) to "unscramble".
+
+### Using a library
+
+In this course, you will use a library called `bcrypt` to do the hashing for
+you. First `gem install bcrypt`. Now you can play in the console:
+
+```ruby
+require 'bcrypt'
+# => true
+password_hash = BCrypt::Password.create('my_secret_password')
+# => "$2a$10$sl.3R32Paf64TqYRU3DBduNJkZMNBsbjyr8WIOdUi/s9TM4VmHNHO"
+password_hash.is_password?('my_secret_password')
+# => true
+password_hash.is_password?('not_my_secret_password')
+# => false
+```
+
+The example above uses the `BCrypt::Password` class; the `::create` factory
+method takes a password and hashes it. You store the resulting
+`BCrypt::Password` object in `password_hash`.
+
+The `BCrypt::Password` class has an instance method, `#is_password?`. The method
+takes a string, hashes the string, and compares it with the `BCrypt::Password`
+contents.
+
+If the argument is the same string as before, the two hashes will be equal and
+`#is_password?` returns true; otherwise it returns false.
+
+### Requiring `bcrypt`
+
+Edit your __Gemfile__ to include `gem "bcrypt"` at the top level.
+
+> **Note:** Rails will include a commented-out version of the `bcrypt` gem in
+> the __Gemfile__ unless you use the `--minimal` flag when creating your
+> project. If you use `--minimal`, Rails will skip `bcrypt` altogether.
+
+## Phase II: `User` model
+
+### Initial columns and indexes
+
+Start with `rails g model User`. Add string columns to the `users` table for
+`username` and `password_digest`. _Digest_ is just another name for a hash. Toss
+an index on `username` too (make it `unique`). Add `null: false` to both columns
+and migrate.
+
+Note that you **will not** store the password itself in the DB; you're going to
+store the hashed version. So you should **NOT** have a `password` column in your
+table.
+
+### Storing/Verifying a password
+
+Go ahead and create a `User` object in the console:
+
+```ruby
+[1] pry(man)> u = User.new
+=> #<User id: nil, username: nil, password_digest: nil, created_at: nil, updated_at: nil>
+[2] pry(man)> u.username = 'earl'
+=> "earl"
+[3] pry(man)> u.password_digest = BCrypt::Password.create('i_love_breakfast')
+=> "$2a$12$mIE28F3HgEFZE35GOEqon.Jp3oISzOhHeBDYZS76sovVUqu5DdLzK"
+[4] pry(man)> u.save
+TRANSACTION (0.3ms)  BEGIN
+  User Exists? (42.4ms)  SELECT 1 AS one FROM "users" WHERE "users"."username" = $1 LIMIT $2  [["username", "earl"], ["LIMIT", 1]]
+  User Create (0.8ms)  INSERT INTO "users" ("username", "password_digest", "created_at", "updated_at") VALUES ($1, $2, $3, $4) RETURNING "id"  [["username", "earl"], ["password_digest", "[FILTERED]"], ["created_at", "2022-06-06 21:53:01.274889"], ["updated_at", "2022-06-06 21:53:01.274889"]]
+  TRANSACTION (43.9ms)  COMMIT
+=> true
+[5] pry(man)> u.password_digest
+=> "$2a$12$mIE28F3HgEFZE35GOEqon.Jp3oISzOhHeBDYZS76sovVUqu5DdLzK"
+```
+
+Here's how to verify that password later:
+
+```ruby
+[6] pry(man)> u = User.first
+User Load (0.3ms)  SELECT "users".* FROM "users" ORDER BY "users"."id" ASC LIMIT $1  [["LIMIT", 1]]
+=> #<User:0x00000001103f2d78
+ id: 1,
+ username: "earl",
+ password_digest: "[FILTERED]",
+ created_at: Mon, 06 Jun 2022 21:53:01.274889000 UTC +00:00,
+ updated_at: Mon, 06 Jun 2022 21:53:01.274889000 UTC +00:00>
+[7] pry(man)> BCrypt::Password.new(u.password_digest).is_password?('i_love_breakfast')
+=> true
+```
+
+Okay, cool. Notice that when you pull down the `User`, `password_digest` is set
+to a string, since that is what the DB stores. You want to get a
+`BCrypt::Password` object back from the digest. Because the digest is **already
+hashed**, you use the `new` constructor rather than the `create` factory method;
+`create` creates a `Password` object by hashing the input, while `new` builds a
+`Password` object from an existing, string-ified hash.
+
+This code is not very convenient. Let's add some helper methods to `User`.
+
+### Write `User#password=` and `User#is_password?`
+
+First write a method that will make it easier to set the `password_digest`
+column. Right now, the programmer is required to hash the password themselves.
+Let's do it for them:
+
+```ruby
+class User < ApplicationRecord
+  def password=(password)
+    self.password_digest = BCrypt::Password.create(password)
+  end
+end
+```
+
+The fact that you don't have a `password` column in the DB does not prevent you
+from writing a setter method named `password=`. This is totally cool. In this
+case, instead of saving the actual password to your database, you're going to
+use BCrypt to hash it and then save it to the `password_digest` column.
+
+Let's also save the programmer from having to do the hard work of verifying a
+password:
+
+```ruby
+class User < ApplicationRecord
+  def password=(password)
+    self.password_digest = BCrypt::Password.create(password)
+  end
+
+  def is_password?(password)
+    BCrypt::Password.new(password_digest).is_password?(password)
+  end
+end
+```
+
+Note that your `is_password?` is calling BCrypt's `is_password?`. Don't confuse
+these two methods. The former is called on a `User` instance; the latter is
+called on a `BCrypt::Password` instance.
+
+Now test it out!
+
+```ruby
+[1] pry(main)> u = User.new
+=> #<User id: nil, username: nil, password_digest: nil, created_at: nil, updated_at: nil>
+[2] pry(main)> u.username = 'Houdini'
+=> "Houdini"
+[3] pry(main)> u.password = 'i_remember_kiki'
+=> "i_remember_kiki"
+[4] pry(main)> u.save
+  TRANSACTION (0.2ms)  BEGIN
+  User Exists? (0.4ms)  SELECT 1 AS one FROM "users" WHERE "users"."username" = $1 LIMIT $2  [["username", "Houdini"], ["LIMIT", 1]]
+  User Create (1.5ms)  INSERT INTO "users" ("username", "password_digest", "created_at", "updated_at") VALUES ($1, $2, $3, $4) RETURNING "id"  [["username", "Houdini"], ["password_digest", "[FILTERED]"], ["created_at", "2022-06-06 22:10:10.324819"], ["updated_at", "2022-06-06 22:10:10.324819"]]
+  TRANSACTION (40.1ms)  COMMIT
+=> true
+[5] pry(main)> u = User.last
+  User Load (0.3ms)  SELECT "users".* FROM "users" ORDER BY "users"."id" DESC LIMIT $1  [["LIMIT", 1]]
+=> #<User:0x00000001105ba1b0
+ id: 2,
+ username: "Houdini",
+ password_digest: "[FILTERED]",
+ created_at: Mon, 06 Jun 2022 22:10:10.324819000 UTC +00:00,
+ updated_at: Mon, 06 Jun 2022 22:10:10.324819000 UTC +00:00>
+[6] pry(main)> u.is_password?('i_remember_kiki')
+=> true
+[7] pry(main)> u.is_password?('random_password_guess')
+=> false
+```
+
+Whoa, object orientation for the win! Hey, did you know it's totally cool to
+write methods on your model objects? You have permission: Go forth and multiply
+methods!
+
+## Phase III: Creating new users
+
+Now add `users` resources for `create`, `new`, and `show` actions--you'll add
+`show` functionality in Part II--and a `UsersController`:
+
+```ruby
+# config/routes.rb
+Rails.application.routes.draw do
+  root "users#new"
+  resources :users, only: %i(create new show)
+end
+
+# app/controllers/users_controller.rb
+class UsersController < ApplicationController
+  def create
+    @user = User.new(user_params)
+
+    if @user.save
+      render json: @user
+    else
+      render json: @user.errors.full_messages
+    end
+  end
+
+  def new
+  end
+
+  private
+
+  def user_params
+    params.require(:user).permit(:username, :password)
+  end
+end
+```
+
+Notice that this code calls `#permit` with `:password`, **not** with
+`password_digest`.  Is this ok?  **Yes**: Just like in your Active Record Lite
+project, mass-assignment will call the setter method `password=`. It's okay that
+this doesn't set a password column.
+
+Add a `new` view, too, so that users can sign up for the site.
+
+```erb
+<!-- app/views/users/new.html.erb -->
+<h1>Sign Up!</h1>
+
+<%= render "shared/form", task: "signup" %>
+
+<!-- app/views/shared/_form.html.erb -->
+<% action = (task == "signup" ? users_url : session_url) %>
+<% message = (task == "signup" ? "Sign Up!" : "Log In!") %>
+
+<form action="<%= action %>" method="POST">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>"
+  >
+  
+  <label for="user_username">Username</label>
+  <input
+    type="text"
+    name="user[username]"
+    id="user_username"
+  >
+  <br>
+
+  <label for="user_password">Password</label>
+  <input 
+    type="password"
+    name="user[password]"
+    id="user_password"
+  >
+  <br>
+
+  <input type="submit" value="<%= message %>">
+</form>
+```
+
+(Note that this form partial anticipates being used for "Login" as well,
+although you won't build out that functionality until Part II.)
+
+### Validating `User`
+
+Okay, you can now create users through the form. You probably want to toss some
+validations on your `User` model:
+
+```ruby
+class User < ActiveRecord::Base
+  validates :username, presence: true, uniqueness: true
+  validates :password_digest, presence: { message: 'Password can\'t be blank' }
+
+  # ...
+end
+```
+
+Notice that you can set your own message to use if the `password_digest` is
+blank. The default is "Password digest can't be blank", but the user won't know
+what a password digest is.
+
+What if you want to validate the length of the password? Right now, you never
+store the password in the `User` object; for that reason, the password will no
+longer be around to check when you eventually validate the `User`. Does it make
+sense why you can't just slap on `validates :password, length: { minimum: 6 }`?
+
+Here's one way to accomplish your goal: store the password in an instance
+variable, but never save this to the DB. First, modify `#password=`:
+
+```ruby
+  def password=(password)
+    @password = password
+    self.password_digest = BCrypt::Password.create(password)
+  end
+```
+
+This saves the password in an instance variable. Active Record **will not** try
+to save the password to the DB, however. Instead, the `@password` instance
+variable will be ignored.
+
+You can now validate the password:
+
+```ruby
+class User < ApplicationRecord
+  attr_reader :password
+
+  validates :username, presence: true
+  validates :password_digest, presence: { message: 'Password can\'t be blank' }
+  validates :password, length: { minimum: 6, allow_nil: true }
+
+  # ...
+end
+```
+
+A couple of notes:
+
+1. The code above adds the `#password` reader method; the validation will call
+   this to check the attribute. Again, validations can check more than just
+   database columns; you can apply a validation to any attribute.
+
+2. It also adds `allow_nil: true`. This means the validation will pass if
+   `@password` is `nil`. This is desirable because the `@password` attribute is
+  set **only if you change the password with `#password=`.** Observe:
+
+   ```ruby
+   [1] pry(main)> User.create!(username: 'houdini', password: 'password')
+     TRANSACTION (0.9ms)  BEGIN
+     User Exists? (0.9ms)  SELECT 1 AS one FROM "users" WHERE "users"."username" = $1 LIMIT $2  [["username", "houdini"], ["LIMIT", 1]]
+     User Create (41.5ms)  INSERT INTO "users" ("username", "password_digest", "created_at", "updated_at") VALUES ($1, $2, $3, $4) RETURNING "id"  [["username", "houdini"], ["password_digest", "[FILTERED]"], ["created_at", "2022-06-07 00:15:08.828165"], ["updated_at", "2022-06-07 00:15:08.828165"]]
+     TRANSACTION (3.1ms)  COMMIT
+   => #<User:0x000000011067f5a0
+    id: 4,
+    username: "houdini",
+    password_digest: "[FILTERED]",
+    created_at: Tue, 07 Jun 2022 00:15:08.828165000 UTC +00:00,
+    updated_at: Tue, 07 Jun 2022 00:15:08.828165000 UTC +00:00>
+   [2] pry(main)> u = User.last
+     User Load (40.3ms)  SELECT "users".* FROM "users" ORDER BY "users"."id" DESC LIMIT $1  [["LIMIT", 1]]
+   => #<User:0x00000001106e4a68
+    id: 4,
+    username: "houdini",
+    password_digest: "[FILTERED]",
+    created_at: Tue, 07 Jun 2022 00:15:08.828165000 UTC +00:00,
+    updated_at: Tue, 07 Jun 2022 00:15:08.828165000 UTC +00:00>
+   [3] pry(main)> u.password
+   => nil
+   [4] pry(main)> u.password_digest
+   => "$2a$12$rHkbhXIZvqeDVZGhu0y0kebflLpRKlVulETTDTXg3p/WRXzUx.Aly"
+   ```
+
+   Notice that the password is no longer set when you fetch `houdini` back from
+   the DB. That's because this attribute only lived in an instance variable that
+   was never going to get persisted to the DB.
+
+   Let's try one more thing:
+
+   ```ruby
+   [5] pry(main)> u.valid?
+   => true
+   ```
+
+   If you didn't `allow_nil: true`, then `houdini` would be marked as invalid
+   because a `password` attribute with a value of `nil` would not meet the
+   length requirement. In reality, you only need to validate the password when
+   it has been changed, which is exactly when `@password` is not `nil`.
+
+[sign-up-diagram]: https://assets.aaonline.io/fullstack/rails/assets/signup_diagram.png
\ No newline at end of file
diff --git a/rails/demos/rails-auth/Rakefile b/rails/demos/rails-auth/Rakefile
new file mode 100644
index 0000000..d298243
--- /dev/null
+++ b/rails/demos/rails-auth/Rakefile
@@ -0,0 +1,6 @@
+# Add your own tasks in files placed in lib/tasks ending in .rake,
+# for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
+
+require_relative "config/application"
+
+Rails.application.load_tasks
\ No newline at end of file
diff --git a/rails/demos/rails-auth/app/assets/config/manifest.js b/rails/demos/rails-auth/app/assets/config/manifest.js
new file mode 100644
index 0000000..f83f92b
--- /dev/null
+++ b/rails/demos/rails-auth/app/assets/config/manifest.js
@@ -0,0 +1,2 @@
+//= link_tree ../images
+//= link_directory ../stylesheets .css
\ No newline at end of file
diff --git a/rails/demos/rails-auth/app/assets/images/.keep b/rails/demos/rails-auth/app/assets/images/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/app/assets/stylesheets/application.css b/rails/demos/rails-auth/app/assets/stylesheets/application.css
new file mode 100644
index 0000000..21c9ac5
--- /dev/null
+++ b/rails/demos/rails-auth/app/assets/stylesheets/application.css
@@ -0,0 +1,15 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS (and SCSS, if configured) file within this directory, lib/assets/stylesheets, or any plugin's
+ * vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree .
+ *= require_self
+ */
\ No newline at end of file
diff --git a/rails/demos/rails-auth/app/controllers/application_controller.rb b/rails/demos/rails-auth/app/controllers/application_controller.rb
new file mode 100644
index 0000000..fc68861
--- /dev/null
+++ b/rails/demos/rails-auth/app/controllers/application_controller.rb
@@ -0,0 +1,22 @@
+class ApplicationController < ActionController::Base
+  helper_method :current_user
+
+  def login!(user)
+    @current_user = user
+    session[:session_token] = user.session_token
+  end
+
+  def current_user
+    return nil if session[:session_token].nil?
+    @current_user ||= User.find_by(session_token: session[:session_token])
+  end
+
+  def logout!
+    current_user.try(:reset_session_token!)
+    session[:session_token] = nil
+  end
+
+  def require_current_user!
+    redirect_to new_session_url if current_user.nil?
+  end
+end
diff --git a/rails/demos/rails-auth/app/controllers/concerns/.keep b/rails/demos/rails-auth/app/controllers/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/app/controllers/sessions_controller.rb b/rails/demos/rails-auth/app/controllers/sessions_controller.rb
new file mode 100644
index 0000000..d92df79
--- /dev/null
+++ b/rails/demos/rails-auth/app/controllers/sessions_controller.rb
@@ -0,0 +1,27 @@
+class SessionsController < ApplicationController
+  def create
+    # signs a user in
+    user = User.find_by_credentials(
+      params[:user][:username],
+      params[:user][:password]
+    )
+
+    if user.nil?
+      # no user with the given username and password!
+      render json: "Invalid credentials".to_json
+    else
+      # sign the user in
+      login!(user)
+      redirect_to user_url(user)
+    end
+  end
+
+  def destroy
+    # sign a user out
+    logout!
+    redirect_to new_session_url
+  end
+
+  def new # presents a login form
+  end
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/app/controllers/users_controller.rb b/rails/demos/rails-auth/app/controllers/users_controller.rb
new file mode 100644
index 0000000..f1d2fb9
--- /dev/null
+++ b/rails/demos/rails-auth/app/controllers/users_controller.rb
@@ -0,0 +1,36 @@
+class UsersController < ApplicationController
+  before_action :require_current_user!, except: %i(create new)
+  before_action :verify_current_user_access, only: %i(show)
+
+  def create
+    # sign up the user
+    @user = User.new(user_params)
+    if @user.save
+      # redirect them to the new user's show page
+      login!(@user)
+      redirect_to user_url(@user)
+    else
+      render json: @user.errors.full_messages
+    end
+  end
+
+  def new # present form for signup
+  end
+
+  def show
+    # show the user's details (just their username)
+    @user = current_user
+  end
+
+  private
+  
+  def user_params
+    params.require(:user).permit(:username, :password)
+  end
+
+  def verify_current_user_access
+    unless current_user.id == params[:id].to_i
+      redirect_to new_session_url
+    end
+  end
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/app/helpers/application_helper.rb b/rails/demos/rails-auth/app/helpers/application_helper.rb
new file mode 100644
index 0000000..de6be79
--- /dev/null
+++ b/rails/demos/rails-auth/app/helpers/application_helper.rb
@@ -0,0 +1,2 @@
+module ApplicationHelper
+end
diff --git a/rails/demos/rails-auth/app/models/application_record.rb b/rails/demos/rails-auth/app/models/application_record.rb
new file mode 100644
index 0000000..b63caeb
--- /dev/null
+++ b/rails/demos/rails-auth/app/models/application_record.rb
@@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+  primary_abstract_class
+end
diff --git a/rails/demos/rails-auth/app/models/concerns/.keep b/rails/demos/rails-auth/app/models/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/app/models/user.rb b/rails/demos/rails-auth/app/models/user.rb
new file mode 100644
index 0000000..7e38587
--- /dev/null
+++ b/rails/demos/rails-auth/app/models/user.rb
@@ -0,0 +1,56 @@
+# == Schema Information
+#
+# Table name: users
+#
+#  id              :bigint           not null, primary key
+#  username        :string           not null
+#  password_digest :string           not null
+#  created_at      :datetime         not null
+#  updated_at      :datetime         not null
+#
+class User < ApplicationRecord
+  attr_reader :password
+
+  validates :username, :session_token, presence: true, uniqueness: true
+  validates :password_digest, presence: { message: 'Password can\'t be blank' }
+  validates :password, length: { minimum: 6, allow_nil: true }
+
+  before_validation :ensure_session_token
+
+  def self.find_by_credentials(username, password)
+    user = User.find_by(username: username)
+    # `user&.is_password?(password)` is syntactic sugar for
+    # `user && user.is_password?(password)`
+    user&.is_password?(password) ? user : nil
+  end
+
+  def password=(password)
+    @password = password
+    self.password_digest = BCrypt::Password.create(password)
+  end
+
+  def is_password?(password)
+    BCrypt::Password.new(password_digest).is_password?(password)
+  end
+
+  def reset_session_token!
+    self.session_token = generate_unique_session_token
+    self.save!
+    self.session_token
+  end
+
+  private
+
+  def generate_unique_session_token
+    # `SecureRandom::urlsafe_base64` does not guarantee uniqueness. Wrapping
+    # this call in a loop ensures that no other user has the generated token.
+    loop do
+      session_token = SecureRandom::urlsafe_base64(16)
+      return session_token unless User.exists?(session_token: session_token)
+    end
+  end
+
+  def ensure_session_token
+    self.session_token ||= generate_unique_session_token
+  end
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/app/views/layouts/application.html.erb b/rails/demos/rails-auth/app/views/layouts/application.html.erb
new file mode 100644
index 0000000..7cf6fcd
--- /dev/null
+++ b/rails/demos/rails-auth/app/views/layouts/application.html.erb
@@ -0,0 +1,31 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>Auth Demo</title>
+    <meta name="viewport" content="width=device-width,initial-scale=1">
+    <%= csrf_meta_tags %>
+    <%= csp_meta_tag %>
+
+    <%= stylesheet_link_tag "application" %>
+  </head>
+
+  <body>
+  
+    <% if !current_user.nil? %>
+      <ul>
+        <li>Logged in as: <%= current_user.username %></li>
+        <li>
+          <form action="<%= session_url %>" method="POST">
+            <input type="hidden"
+                  name="authenticity_token"
+                  value="<%= form_authenticity_token %>">
+            <input type="hidden" value="delete" name="_method" />
+            <input type="submit" value="Logout" />
+          </form>
+        </li>
+      </ul>
+    <% end %>
+
+    <%= yield %>
+  </body>
+</html>
diff --git a/rails/demos/rails-auth/app/views/sessions/new.html.erb b/rails/demos/rails-auth/app/views/sessions/new.html.erb
new file mode 100644
index 0000000..2a20abb
--- /dev/null
+++ b/rails/demos/rails-auth/app/views/sessions/new.html.erb
@@ -0,0 +1,3 @@
+<h1>Log in!</h1>
+
+<%= render "shared/form", task: "login" %>
diff --git a/rails/demos/rails-auth/app/views/shared/_form.html.erb b/rails/demos/rails-auth/app/views/shared/_form.html.erb
new file mode 100644
index 0000000..9de719c
--- /dev/null
+++ b/rails/demos/rails-auth/app/views/shared/_form.html.erb
@@ -0,0 +1,28 @@
+<% action = (task == "signup" ? users_url : session_url) %>
+<% message = (task == "signup" ? "Sign Up!" : "Log In!") %>
+
+<form action="<%= action %>" method="POST">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>"
+  >
+  
+  <label for="user_username">Username</label>
+  <input
+    type="text"
+    name="user[username]"
+    id="user_username"
+  >
+  <br>
+
+  <label for="user_password">Password</label>
+  <input 
+    type="password"
+    name="user[password]"
+    id="user_password"
+  >
+  <br>
+
+  <input type="submit" value="<%= message %>">
+</form>
diff --git a/rails/demos/rails-auth/app/views/users/new.html.erb b/rails/demos/rails-auth/app/views/users/new.html.erb
new file mode 100644
index 0000000..3461e10
--- /dev/null
+++ b/rails/demos/rails-auth/app/views/users/new.html.erb
@@ -0,0 +1,3 @@
+<h1>Sign up!</h1>
+
+<%= render "shared/form", task: "signup" %>
diff --git a/rails/demos/rails-auth/app/views/users/show.html.erb b/rails/demos/rails-auth/app/views/users/show.html.erb
new file mode 100644
index 0000000..bfcb72e
--- /dev/null
+++ b/rails/demos/rails-auth/app/views/users/show.html.erb
@@ -0,0 +1,3 @@
+<h1><%= @user.username %></h1>
+
+<p>Hello, dear user!</p>
diff --git a/rails/demos/rails-auth/bin/bundle b/rails/demos/rails-auth/bin/bundle
new file mode 100644
index 0000000..2060668
--- /dev/null
+++ b/rails/demos/rails-auth/bin/bundle
@@ -0,0 +1,114 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'bundle' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "rubygems"
+
+m = Module.new do
+  module_function
+
+  def invoked_as_script?
+    File.expand_path($0) == File.expand_path(__FILE__)
+  end
+
+  def env_var_version
+    ENV["BUNDLER_VERSION"]
+  end
+
+  def cli_arg_version
+    return unless invoked_as_script? # don't want to hijack other binstubs
+    return unless "update".start_with?(ARGV.first || " ") # must be running `bundle update`
+    bundler_version = nil
+    update_index = nil
+    ARGV.each_with_index do |a, i|
+      if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
+        bundler_version = a
+      end
+      next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
+      bundler_version = $1
+      update_index = i
+    end
+    bundler_version
+  end
+
+  def gemfile
+    gemfile = ENV["BUNDLE_GEMFILE"]
+    return gemfile if gemfile && !gemfile.empty?
+
+    File.expand_path("../Gemfile", __dir__)
+  end
+
+  def lockfile
+    lockfile =
+      case File.basename(gemfile)
+      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
+      else "#{gemfile}.lock"
+      end
+    File.expand_path(lockfile)
+  end
+
+  def lockfile_version
+    return unless File.file?(lockfile)
+    lockfile_contents = File.read(lockfile)
+    return unless lockfile_contents =~ /\n\nBUNDLED WITH\n\s{2,}(#{Gem::Version::VERSION_PATTERN})\n/
+    Regexp.last_match(1)
+  end
+
+  def bundler_requirement
+    @bundler_requirement ||=
+      env_var_version || cli_arg_version ||
+        bundler_requirement_for(lockfile_version)
+  end
+
+  def bundler_requirement_for(version)
+    return "#{Gem::Requirement.default}.a" unless version
+
+    bundler_gem_version = Gem::Version.new(version)
+
+    requirement = bundler_gem_version.approximate_recommendation
+
+    return requirement unless Gem.rubygems_version < Gem::Version.new("2.7.0")
+
+    requirement += ".a" if bundler_gem_version.prerelease?
+
+    requirement
+  end
+
+  def load_bundler!
+    ENV["BUNDLE_GEMFILE"] ||= gemfile
+
+    activate_bundler
+  end
+
+  def activate_bundler
+    gem_error = activation_error_handling do
+      gem "bundler", bundler_requirement
+    end
+    return if gem_error.nil?
+    require_error = activation_error_handling do
+      require "bundler/version"
+    end
+    return if require_error.nil? && Gem::Requirement.new(bundler_requirement).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+    warn "Activating bundler (#{bundler_requirement}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_requirement}'`"
+    exit 42
+  end
+
+  def activation_error_handling
+    yield
+    nil
+  rescue StandardError, LoadError => e
+    e
+  end
+end
+
+m.load_bundler!
+
+if m.invoked_as_script?
+  load Gem.bin_path("bundler", "bundle")
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/bin/rails b/rails/demos/rails-auth/bin/rails
new file mode 100644
index 0000000..fa3c01a
--- /dev/null
+++ b/rails/demos/rails-auth/bin/rails
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+APP_PATH = File.expand_path("../config/application", __dir__)
+require_relative "../config/boot"
+require "rails/commands"
\ No newline at end of file
diff --git a/rails/demos/rails-auth/bin/rake b/rails/demos/rails-auth/bin/rake
new file mode 100644
index 0000000..19d605d
--- /dev/null
+++ b/rails/demos/rails-auth/bin/rake
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+require_relative "../config/boot"
+require "rake"
+Rake.application.run
\ No newline at end of file
diff --git a/rails/demos/rails-auth/bin/setup b/rails/demos/rails-auth/bin/setup
new file mode 100644
index 0000000..9bd670f
--- /dev/null
+++ b/rails/demos/rails-auth/bin/setup
@@ -0,0 +1,33 @@
+#!/usr/bin/env ruby
+require "fileutils"
+
+# path to your application root.
+APP_ROOT = File.expand_path("..", __dir__)
+
+def system!(*args)
+  system(*args) || abort("\n== Command #{args} failed ==")
+end
+
+FileUtils.chdir APP_ROOT do
+  # This script is a way to set up or update your development environment automatically.
+  # This script is idempotent, so that you can run it at any time and get an expectable outcome.
+  # Add necessary setup steps to this file.
+
+  puts "== Installing dependencies =="
+  system! "gem install bundler --conservative"
+  system("bundle check") || system!("bundle install")
+
+  # puts "\n== Copying sample files =="
+  # unless File.exist?("config/database.yml")
+  #   FileUtils.cp "config/database.yml.sample", "config/database.yml"
+  # end
+
+  puts "\n== Preparing database =="
+  system! "bin/rails db:prepare"
+
+  puts "\n== Removing old logs and tempfiles =="
+  system! "bin/rails log:clear tmp:clear"
+
+  puts "\n== Restarting application server =="
+  system! "bin/rails restart"
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config.ru b/rails/demos/rails-auth/config.ru
new file mode 100644
index 0000000..38cc27a
--- /dev/null
+++ b/rails/demos/rails-auth/config.ru
@@ -0,0 +1,6 @@
+# This file is used by Rack-based servers to start the application.
+
+require_relative "config/environment"
+
+run Rails.application
+Rails.application.load_server
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/application.rb b/rails/demos/rails-auth/config/application.rb
new file mode 100644
index 0000000..f38225f
--- /dev/null
+++ b/rails/demos/rails-auth/config/application.rb
@@ -0,0 +1,37 @@
+require_relative "boot"
+
+require "rails"
+# Pick the frameworks you want:
+require "active_model/railtie"
+# require "active_job/railtie"
+require "active_record/railtie"
+# require "active_storage/engine"
+require "action_controller/railtie"
+# require "action_mailer/railtie"
+# require "action_mailbox/engine"
+# require "action_text/engine"
+require "action_view/railtie"
+# require "action_cable/engine"
+# require "rails/test_unit/railtie"
+
+# Require the gems listed in Gemfile, including any gems
+# you've limited to :test, :development, or :production.
+Bundler.require(*Rails.groups)
+
+module AuthDemo
+  class Application < Rails::Application
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults 7.0
+
+    # Configuration for the application, engines, and railties goes here.
+    #
+    # These settings can be overridden in specific environments using the files
+    # in config/environments, which are processed later.
+    #
+    # config.time_zone = "Central Time (US & Canada)"
+    # config.eager_load_paths << Rails.root.join("extras")
+
+    # Don't generate system test files.
+    config.generators.system_tests = nil
+  end
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/boot.rb b/rails/demos/rails-auth/config/boot.rb
new file mode 100644
index 0000000..2820116
--- /dev/null
+++ b/rails/demos/rails-auth/config/boot.rb
@@ -0,0 +1,3 @@
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+
+require "bundler/setup" # Set up gems listed in the Gemfile.
diff --git a/rails/demos/rails-auth/config/credentials.yml.enc b/rails/demos/rails-auth/config/credentials.yml.enc
new file mode 100644
index 0000000..ae07584
--- /dev/null
+++ b/rails/demos/rails-auth/config/credentials.yml.enc
@@ -0,0 +1 @@
+ifCpsyidyfFtfTqT9ZdIDRTFFo5Xg58fTwxwyNFBItrrfpR5Nc+Ia3FjD+fT42rUGb9l3rkhK7p3QNkD03mltCgjSSRaCx4ZkE48h6RqzkcMRJCWiq3yCPyVMFWgKp4WUYcJBDqXst1udXI1QTmpsQaBd6vpP8lLrDZM6HMDjbdPWNexY5nZMtkGTO+Kv0MOO5YS+Wb2qnTPsfGgGa79YUz4WfAm/AakwjtV9fkY2fZzju2iWUg9B6A7HS3BjTyGmkh9y1Jfa7yzQM7aHVhQMlFWTRJLOpNf/U52b7Md6848GI/yVEnnpAu7yYGk077tgUODXKsQczDWCxrhfYFkH/JEwKlDvsswLi+H+3xIn+E+eucUL4eMEN6AzThwKx3I1nCeSBOxSCcI5FYomuiExF74iTrsr5+zXZri--tgzGKc1BMSpNcy7s--X8J2KoG4+jPnafmy5v2o2g==
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/database.yml b/rails/demos/rails-auth/config/database.yml
new file mode 100644
index 0000000..95471dc
--- /dev/null
+++ b/rails/demos/rails-auth/config/database.yml
@@ -0,0 +1,86 @@
+# PostgreSQL. Versions 9.3 and up are supported.
+#
+# Install the pg driver:
+#   gem install pg
+# On macOS with Homebrew:
+#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
+# On macOS with MacPorts:
+#   gem install pg -- --with-pg-config=/opt/local/lib/postgresql84/bin/pg_config
+# On Windows:
+#   gem install pg
+#       Choose the win32 build.
+#       Install PostgreSQL and put its /bin directory on your path.
+#
+# Configure Using Gemfile
+# gem "pg"
+#
+default: &default
+  adapter: postgresql
+  encoding: unicode
+  # For details on connection pooling, see Rails configuration guide
+  # https://guides.rubyonrails.org/configuring.html#database-pooling
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+
+development:
+  <<: *default
+  database: auth_demo_development
+
+  # The specified database role being used to connect to postgres.
+  # To create additional roles in postgres see `$ createuser --help`.
+  # When left blank, postgres will use the default role. This is
+  # the same name as the operating system user running Rails.
+  #username: auth_demo
+
+  # The password associated with the postgres role (username).
+  #password:
+
+  # Connect on a TCP socket. Omitted by default since the client uses a
+  # domain socket that doesn't need configuration. Windows does not have
+  # domain sockets, so uncomment these lines.
+  #host: localhost
+
+  # The TCP port the server listens on. Defaults to 5432.
+  # If your server runs on a different port number, change accordingly.
+  #port: 5432
+
+  # Schema search path. The server defaults to $user,public
+  #schema_search_path: myapp,sharedapp,public
+
+  # Minimum log levels, in increasing order:
+  #   debug5, debug4, debug3, debug2, debug1,
+  #   log, notice, warning, error, fatal, and panic
+  # Defaults to warning.
+  #min_messages: notice
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: auth_demo_test
+
+# As with config/credentials.yml, you never want to store sensitive information,
+# like your database password, in your source code. If your source code is
+# ever seen by anyone, they now have access to your database.
+#
+# Instead, provide the password or a full connection URL as an environment
+# variable when you boot the app. For example:
+#
+#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
+#
+# If the connection URL is provided in the special DATABASE_URL environment
+# variable, Rails will automatically merge its configuration values on top of
+# the values provided in this file. Alternatively, you can specify a connection
+# URL environment variable explicitly:
+#
+#   production:
+#     url: <%= ENV["MY_APP_DATABASE_URL"] %>
+#
+# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
+# for a full overview on how database connection configuration can be specified.
+#
+production:
+  <<: *default
+  database: auth_demo_production
+  username: auth_demo
+  password: <%= ENV["AUTH_DEMO_DATABASE_PASSWORD"] %>
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/environment.rb b/rails/demos/rails-auth/config/environment.rb
new file mode 100644
index 0000000..445c788
--- /dev/null
+++ b/rails/demos/rails-auth/config/environment.rb
@@ -0,0 +1,5 @@
+# Load the Rails application.
+require_relative "application"
+
+# Initialize the Rails application.
+Rails.application.initialize!
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/environments/development.rb b/rails/demos/rails-auth/config/environments/development.rb
new file mode 100644
index 0000000..851adc5
--- /dev/null
+++ b/rails/demos/rails-auth/config/environments/development.rb
@@ -0,0 +1,62 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # In the development environment your application's code is reloaded any time
+  # it changes. This slows down response time but is perfect for development
+  # since you don't have to restart the web server when you make code changes.
+  config.cache_classes = false
+
+  # Do not eager load code on boot.
+  config.eager_load = false
+
+  # Show full error reports.
+  config.consider_all_requests_local = true
+
+  # Enable server timing
+  config.server_timing = true
+
+  # Enable/disable caching. By default caching is disabled.
+  # Run rails dev:cache to toggle caching.
+  if Rails.root.join("tmp/caching-dev.txt").exist?
+    config.action_controller.perform_caching = true
+    config.action_controller.enable_fragment_cache_logging = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      "Cache-Control" => "public, max-age=#{2.days.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
+
+  # Print deprecation notices to the Rails logger.
+  config.active_support.deprecation = :log
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raise an error on page load if there are pending migrations.
+  config.active_record.migration_error = :page_load
+
+  # Highlight code that triggered database queries in logs.
+  config.active_record.verbose_query_logs = true
+
+  # Suppress logger output for asset requests.
+  config.assets.quiet = true
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+
+  # Uncomment if you wish to allow Action Cable access from any origin.
+  # config.action_cable.disable_request_forgery_protection = true
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/environments/production.rb b/rails/demos/rails-auth/config/environments/production.rb
new file mode 100644
index 0000000..6aee001
--- /dev/null
+++ b/rails/demos/rails-auth/config/environments/production.rb
@@ -0,0 +1,75 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Code is not reloaded between requests.
+  config.cache_classes = true
+
+  # Eager load code on boot. This eager loads most of Rails and
+  # your application in memory, allowing both threaded web servers
+  # and those relying on copy on write to perform better.
+  # Rake tasks automatically ignore this option for performance.
+  config.eager_load = true
+
+  # Full error reports are disabled and caching is turned on.
+  config.consider_all_requests_local       = false
+  config.action_controller.perform_caching = true
+
+  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  # config.require_master_key = true
+
+  # Disable serving static files from the `/public` folder by default since
+  # Apache or NGINX already handles this.
+  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
+
+  # Compress CSS using a preprocessor.
+  # config.assets.css_compressor = :sass
+
+  # Do not fallback to assets pipeline if a precompiled asset is missed.
+  config.assets.compile = false
+
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.asset_host = "http://assets.example.com"
+
+  # Specifies the header that your server uses for sending files.
+  # config.action_dispatch.x_sendfile_header = "X-Sendfile" # for Apache
+  # config.action_dispatch.x_sendfile_header = "X-Accel-Redirect" # for NGINX
+
+  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
+  # config.force_ssl = true
+
+  # Include generic and useful information about system operation, but avoid logging too much
+  # information to avoid inadvertent exposure of personally identifiable information (PII).
+  config.log_level = :info
+
+  # Prepend all log lines with the following tags.
+  config.log_tags = [ :request_id ]
+
+  # Use a different cache store in production.
+  # config.cache_store = :mem_cache_store
+
+  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
+  # the I18n.default_locale when a translation cannot be found).
+  config.i18n.fallbacks = true
+
+  # Don't log any deprecations.
+  config.active_support.report_deprecations = false
+
+  # Use default logging formatter so that PID and timestamp are not suppressed.
+  config.log_formatter = ::Logger::Formatter.new
+
+  # Use a different logger for distributed setups.
+  # require "syslog/logger"
+  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
+
+  if ENV["RAILS_LOG_TO_STDOUT"].present?
+    logger           = ActiveSupport::Logger.new(STDOUT)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/environments/test.rb b/rails/demos/rails-auth/config/environments/test.rb
new file mode 100644
index 0000000..da62dfc
--- /dev/null
+++ b/rails/demos/rails-auth/config/environments/test.rb
@@ -0,0 +1,50 @@
+require "active_support/core_ext/integer/time"
+
+# The test environment is used exclusively to run your application's
+# test suite. You never need to work with it otherwise. Remember that
+# your test database is "scratch space" for the test suite and is wiped
+# and recreated between test runs. Don't rely on the data there!
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Turn false under Spring and add config.action_view.cache_template_loading = true.
+  config.cache_classes = true
+
+  # Eager loading loads your whole application. When running a single test locally,
+  # this probably isn't necessary. It's a good idea to do in a continuous integration
+  # system, or in some way before deploying your code.
+  config.eager_load = ENV["CI"].present?
+
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = {
+    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
+  }
+
+  # Show full error reports and disable caching.
+  config.consider_all_requests_local       = true
+  config.action_controller.perform_caching = false
+  config.cache_store = :null_store
+
+  # Raise exceptions instead of rendering exception templates.
+  config.action_dispatch.show_exceptions = false
+
+  # Disable request forgery protection in test environment.
+  config.action_controller.allow_forgery_protection = false
+
+  # Print deprecation notices to the stderr.
+  config.active_support.deprecation = :stderr
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/initializers/assets.rb b/rails/demos/rails-auth/config/initializers/assets.rb
new file mode 100644
index 0000000..bd8332f
--- /dev/null
+++ b/rails/demos/rails-auth/config/initializers/assets.rb
@@ -0,0 +1,12 @@
+# Be sure to restart your server when you modify this file.
+
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = "1.0"
+
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/initializers/content_security_policy.rb b/rails/demos/rails-auth/config/initializers/content_security_policy.rb
new file mode 100644
index 0000000..b713b2f
--- /dev/null
+++ b/rails/demos/rails-auth/config/initializers/content_security_policy.rb
@@ -0,0 +1,25 @@
+# Be sure to restart your server when you modify this file.
+
+# Define an application-wide content security policy.
+# See the Securing Rails Applications Guide for more information:
+# https://guides.rubyonrails.org/security.html#content-security-policy-header
+
+# Rails.application.configure do
+#   config.content_security_policy do |policy|
+#     policy.default_src :self, :https
+#     policy.font_src    :self, :https, :data
+#     policy.img_src     :self, :https, :data
+#     policy.object_src  :none
+#     policy.script_src  :self, :https
+#     policy.style_src   :self, :https
+#     # Specify URI for violation reports
+#     # policy.report_uri "/csp-violation-report-endpoint"
+#   end
+#
+#   # Generate session nonces for permitted importmap and inline scripts
+#   config.content_security_policy_nonce_generator = ->(request) { request.session.id.to_s }
+#   config.content_security_policy_nonce_directives = %w(script-src)
+#
+#   # Report violations without enforcing the policy.
+#   # config.content_security_policy_report_only = true
+# end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/initializers/filter_parameter_logging.rb b/rails/demos/rails-auth/config/initializers/filter_parameter_logging.rb
new file mode 100644
index 0000000..b4db5f6
--- /dev/null
+++ b/rails/demos/rails-auth/config/initializers/filter_parameter_logging.rb
@@ -0,0 +1,8 @@
+# Be sure to restart your server when you modify this file.
+
+# Configure parameters to be filtered from the log file. Use this to limit dissemination of
+# sensitive information. See the ActiveSupport::ParameterFilter documentation for supported
+# notations and behaviors.
+Rails.application.config.filter_parameters += [
+  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
+]
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/initializers/inflections.rb b/rails/demos/rails-auth/config/initializers/inflections.rb
new file mode 100644
index 0000000..df431d7
--- /dev/null
+++ b/rails/demos/rails-auth/config/initializers/inflections.rb
@@ -0,0 +1,16 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new inflection rules using the following format. Inflections
+# are locale specific, and you may define rules for as many different
+# locales as you wish. All of these examples are active by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.plural /^(ox)$/i, "\\1en"
+#   inflect.singular /^(ox)en/i, "\\1"
+#   inflect.irregular "person", "people"
+#   inflect.uncountable %w( fish sheep )
+# end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym "RESTful"
+# end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/initializers/permissions_policy.rb b/rails/demos/rails-auth/config/initializers/permissions_policy.rb
new file mode 100644
index 0000000..dd30019
--- /dev/null
+++ b/rails/demos/rails-auth/config/initializers/permissions_policy.rb
@@ -0,0 +1,11 @@
+# Define an application-wide HTTP permissions policy. For further
+# information see https://developers.google.com/web/updates/2018/06/feature-policy
+#
+# Rails.application.config.permissions_policy do |f|
+#   f.camera      :none
+#   f.gyroscope   :none
+#   f.microphone  :none
+#   f.usb         :none
+#   f.fullscreen  :self
+#   f.payment     :self, "https://secure.example.com"
+# end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/locales/en.yml b/rails/demos/rails-auth/config/locales/en.yml
new file mode 100644
index 0000000..30c9973
--- /dev/null
+++ b/rails/demos/rails-auth/config/locales/en.yml
@@ -0,0 +1,33 @@
+# Files in the config/locales directory are used for internationalization
+# and are automatically loaded by Rails. If you want to use locales other
+# than English, add the necessary files in this directory.
+#
+# To use the locales, use `I18n.t`:
+#
+#     I18n.t "hello"
+#
+# In views, this is aliased to just `t`:
+#
+#     <%= t("hello") %>
+#
+# To use a different locale, set it with `I18n.locale`:
+#
+#     I18n.locale = :es
+#
+# This would use the information in config/locales/es.yml.
+#
+# The following keys must be escaped otherwise they will not be retrieved by
+# the default I18n backend:
+#
+# true, false, on, off, yes, no
+#
+# Instead, surround them with single quotes.
+#
+# en:
+#   "true": "foo"
+#
+# To learn more, please read the Rails Internationalization guide
+# available at https://guides.rubyonrails.org/i18n.html.
+
+en:
+  hello: "Hello world"
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/puma.rb b/rails/demos/rails-auth/config/puma.rb
new file mode 100644
index 0000000..411b18d
--- /dev/null
+++ b/rails/demos/rails-auth/config/puma.rb
@@ -0,0 +1,43 @@
+# Puma can serve each request in a thread from an internal thread pool.
+# The `threads` method setting takes two numbers: a minimum and maximum.
+# Any libraries that use thread pools should be configured to match
+# the maximum value specified for Puma. Default is set to 5 threads for minimum
+# and maximum; this matches the default thread size of Active Record.
+#
+max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
+min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count }
+threads min_threads_count, max_threads_count
+
+# Specifies the `worker_timeout` threshold that Puma will use to wait before
+# terminating a worker in development environments.
+#
+worker_timeout 3600 if ENV.fetch("RAILS_ENV", "development") == "development"
+
+# Specifies the `port` that Puma will listen on to receive requests; default is 3000.
+#
+port ENV.fetch("PORT") { 3000 }
+
+# Specifies the `environment` that Puma will run in.
+#
+environment ENV.fetch("RAILS_ENV") { "development" }
+
+# Specifies the `pidfile` that Puma will use.
+pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
+
+# Specifies the number of `workers` to boot in clustered mode.
+# Workers are forked web server processes. If using threads and workers together
+# the concurrency of the application would be max `threads` * `workers`.
+# Workers do not work on JRuby or Windows (both of which do not support
+# processes).
+#
+# workers ENV.fetch("WEB_CONCURRENCY") { 2 }
+
+# Use the `preload_app!` method when specifying a `workers` number.
+# This directive tells Puma to first boot the application and load code
+# before forking the application. This takes advantage of Copy On Write
+# process behavior so workers use less memory.
+#
+# preload_app!
+
+# Allow puma to be restarted by `bin/rails restart` command.
+plugin :tmp_restart
\ No newline at end of file
diff --git a/rails/demos/rails-auth/config/routes.rb b/rails/demos/rails-auth/config/routes.rb
new file mode 100644
index 0000000..46b1cfa
--- /dev/null
+++ b/rails/demos/rails-auth/config/routes.rb
@@ -0,0 +1,8 @@
+Rails.application.routes.draw do
+  # Define your application routes per the DSL in https://guides.rubyonrails.org/routing.html
+
+  # Defines the root path route ("/")
+  root "users#new"
+  resources :users, only: %i(create new show)
+  resource :session, only: %i(create destroy new)
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/db/migrate/20220608153843_create_users.rb b/rails/demos/rails-auth/db/migrate/20220608153843_create_users.rb
new file mode 100644
index 0000000..0ccc21b
--- /dev/null
+++ b/rails/demos/rails-auth/db/migrate/20220608153843_create_users.rb
@@ -0,0 +1,11 @@
+class CreateUsers < ActiveRecord::Migration[7.0]
+  def change
+    create_table :users do |t|
+      t.string :username, null: false
+      t.string :password_digest, null: false
+
+      t.timestamps
+    end
+    add_index :users, :username, unique: true
+  end
+end
diff --git a/rails/demos/rails-auth/db/migrate/20220608183505_add_session_token_to_users.rb b/rails/demos/rails-auth/db/migrate/20220608183505_add_session_token_to_users.rb
new file mode 100644
index 0000000..cb6579c
--- /dev/null
+++ b/rails/demos/rails-auth/db/migrate/20220608183505_add_session_token_to_users.rb
@@ -0,0 +1,6 @@
+class AddSessionTokenToUsers < ActiveRecord::Migration[7.0]
+  def change
+    add_column :users, :session_token, :string, null: false
+    add_index :users, :session_token, unique: true
+  end
+end
diff --git a/rails/demos/rails-auth/db/schema.rb b/rails/demos/rails-auth/db/schema.rb
new file mode 100644
index 0000000..13bf8fa
--- /dev/null
+++ b/rails/demos/rails-auth/db/schema.rb
@@ -0,0 +1,27 @@
+# This file is auto-generated from the current state of the database. Instead
+# of editing this file, please use the migrations feature of Active Record to
+# incrementally modify your database, and then regenerate this schema definition.
+#
+# This file is the source Rails uses to define your schema when running `bin/rails
+# db:schema:load`. When creating a new database, `bin/rails db:schema:load` tends to
+# be faster and is potentially less error prone than running all of your
+# migrations from scratch. Old migrations may fail to apply correctly if those
+# migrations use external dependencies or application code.
+#
+# It's strongly recommended that you check this file into your version control system.
+
+ActiveRecord::Schema[7.0].define(version: 2022_06_08_183505) do
+  # These are extensions that must be enabled in order to support this database
+  enable_extension "plpgsql"
+
+  create_table "users", force: :cascade do |t|
+    t.string "username", null: false
+    t.string "password_digest", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.string "session_token", null: false
+    t.index ["session_token"], name: "index_users_on_session_token", unique: true
+    t.index ["username"], name: "index_users_on_username", unique: true
+  end
+
+end
\ No newline at end of file
diff --git a/rails/demos/rails-auth/db/seeds.rb b/rails/demos/rails-auth/db/seeds.rb
new file mode 100644
index 0000000..555c37c
--- /dev/null
+++ b/rails/demos/rails-auth/db/seeds.rb
@@ -0,0 +1,7 @@
+# This file should contain all the record creation needed to seed the database with its default values.
+# The data can then be loaded with the bin/rails db:seed command (or created alongside the database with db:setup).
+#
+# Examples:
+#
+#   movies = Movie.create([{ name: "Star Wars" }, { name: "Lord of the Rings" }])
+#   Character.create(name: "Luke", movie: movies.first)
\ No newline at end of file
diff --git a/rails/demos/rails-auth/lib/assets/.keep b/rails/demos/rails-auth/lib/assets/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/lib/tasks/.keep b/rails/demos/rails-auth/lib/tasks/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/log/.keep b/rails/demos/rails-auth/log/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/public/404.html b/rails/demos/rails-auth/public/404.html
new file mode 100644
index 0000000..cb93ac7
--- /dev/null
+++ b/rails/demos/rails-auth/public/404.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The page you were looking for doesn't exist (404)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/404.html -->
+  <div class="dialog">
+    <div>
+      <h1>The page you were looking for doesn't exist.</h1>
+      <p>You may have mistyped the address or the page may have moved.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/demos/rails-auth/public/422.html b/rails/demos/rails-auth/public/422.html
new file mode 100644
index 0000000..aa1a374
--- /dev/null
+++ b/rails/demos/rails-auth/public/422.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The change you wanted was rejected (422)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/422.html -->
+  <div class="dialog">
+    <div>
+      <h1>The change you wanted was rejected.</h1>
+      <p>Maybe you tried to change something you didn't have access to.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/demos/rails-auth/public/500.html b/rails/demos/rails-auth/public/500.html
new file mode 100644
index 0000000..0fd6fca
--- /dev/null
+++ b/rails/demos/rails-auth/public/500.html
@@ -0,0 +1,66 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>We're sorry, but something went wrong (500)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/500.html -->
+  <div class="dialog">
+    <div>
+      <h1>We're sorry, but something went wrong.</h1>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/demos/rails-auth/public/apple-touch-icon-precomposed.png b/rails/demos/rails-auth/public/apple-touch-icon-precomposed.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/public/apple-touch-icon.png b/rails/demos/rails-auth/public/apple-touch-icon.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/public/favicon.ico b/rails/demos/rails-auth/public/favicon.ico
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/public/robots.txt b/rails/demos/rails-auth/public/robots.txt
new file mode 100644
index 0000000..0285b2d
--- /dev/null
+++ b/rails/demos/rails-auth/public/robots.txt
@@ -0,0 +1 @@
+# See https://www.robotstxt.org/robotstxt.html for documentation on how to use the robots.txt file
\ No newline at end of file
diff --git a/rails/demos/rails-auth/tmp/.keep b/rails/demos/rails-auth/tmp/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/tmp/pids/.keep b/rails/demos/rails-auth/tmp/pids/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/demos/rails-auth/vendor/.keep b/rails/demos/rails-auth/vendor/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/.gitattributes b/rails/homeworks/capybara/.gitattributes
new file mode 100644
index 0000000..34fb547
--- /dev/null
+++ b/rails/homeworks/capybara/.gitattributes
@@ -0,0 +1,7 @@
+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
\ No newline at end of file
diff --git a/rails/homeworks/capybara/.gitignore b/rails/homeworks/capybara/.gitignore
new file mode 100644
index 0000000..4f0da6f
--- /dev/null
+++ b/rails/homeworks/capybara/.gitignore
@@ -0,0 +1,26 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
\ No newline at end of file
diff --git a/rails/homeworks/capybara/.ruby-version b/rails/homeworks/capybara/.ruby-version
new file mode 100644
index 0000000..94ff29c
--- /dev/null
+++ b/rails/homeworks/capybara/.ruby-version
@@ -0,0 +1 @@
+3.1.1
diff --git a/rails/homeworks/capybara/Gemfile b/rails/homeworks/capybara/Gemfile
new file mode 100644
index 0000000..bfcc811
--- /dev/null
+++ b/rails/homeworks/capybara/Gemfile
@@ -0,0 +1,36 @@
+source "https://rubygems.org"
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+ruby "3.1.1"
+
+gem "bcrypt"
+gem "sassc-rails"
+
+# Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
+gem "rails", "~> 7.0.3"
+
+# The original asset pipeline for Rails [https://github.com/rails/sprockets-rails]
+gem "sprockets-rails"
+
+# Use postgresql as the database for Active Record
+gem "pg", "~> 1.1"
+
+# Use the Puma web server [https://github.com/puma/puma]
+gem "puma", "~> 5.0"
+
+# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
+gem "tzinfo-data", platforms: %i[ mingw mswin x64_mingw jruby ]
+
+group :development, :test do
+  # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
+  gem "byebug", platforms: %i[ mri mingw x64_mingw ]
+end
+
+group :development do
+  # Speed up commands on slow machines / big apps [https://github.com/rails/spring]
+  # gem "spring"
+  gem "annotate"
+  gem "pry-rails"
+  gem "better_errors"
+  gem "binding_of_caller"
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/Gemfile.lock b/rails/homeworks/capybara/Gemfile.lock
new file mode 100644
index 0000000..29bd2f4
--- /dev/null
+++ b/rails/homeworks/capybara/Gemfile.lock
@@ -0,0 +1,258 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailbox (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (>= 2.7.1)
+      net-imap
+      net-pop
+      net-smtp
+    actionmailer (7.0.3)
+      actionpack (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (~> 2.5, >= 2.5.4)
+      net-imap
+      net-pop
+      net-smtp
+      rails-dom-testing (~> 2.0)
+    actionpack (7.0.3)
+      actionview (= 7.0.3)
+      activesupport (= 7.0.3)
+      rack (~> 2.0, >= 2.2.0)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (7.0.3)
+      actionpack (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.6.0)
+      nokogiri (>= 1.8.5)
+    actionview (7.0.3)
+      activesupport (= 7.0.3)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.3.6)
+    activemodel (7.0.3)
+      activesupport (= 7.0.3)
+    activerecord (7.0.3)
+      activemodel (= 7.0.3)
+      activesupport (= 7.0.3)
+    activestorage (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activesupport (= 7.0.3)
+      marcel (~> 1.0)
+      mini_mime (>= 1.1.0)
+    activesupport (7.0.3)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+    addressable (2.8.0)
+      public_suffix (>= 2.0.2, < 5.0)
+    annotate (3.2.0)
+      activerecord (>= 3.2, < 8.0)
+      rake (>= 10.4, < 14.0)
+    bcrypt (3.1.18)
+    better_errors (2.9.1)
+      coderay (>= 1.0.0)
+      erubi (>= 1.0.0)
+      rack (>= 0.9.0)
+    binding_of_caller (1.0.0)
+      debug_inspector (>= 0.0.1)
+    builder (3.2.4)
+    byebug (11.1.3)
+    capybara (3.37.1)
+      addressable
+      matrix
+      mini_mime (>= 0.1.3)
+      nokogiri (~> 1.8)
+      rack (>= 1.6.0)
+      rack-test (>= 0.6.3)
+      regexp_parser (>= 1.5, < 3.0)
+      xpath (~> 3.2)
+    childprocess (4.1.0)
+    coderay (1.1.3)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    debug_inspector (1.1.0)
+    diff-lcs (1.5.0)
+    digest (3.1.0)
+    erubi (1.10.0)
+    ffi (1.15.5)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
+      concurrent-ruby (~> 1.0)
+    loofah (2.18.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (1.0.2)
+    matrix (0.4.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    minitest (5.16.1)
+    net-imap (0.2.3)
+      digest
+      net-protocol
+      strscan
+    net-pop (0.1.1)
+      digest
+      net-protocol
+      timeout
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    pg (1.4.0)
+    pry (0.14.1)
+      coderay (~> 1.1)
+      method_source (~> 1.0)
+    pry-rails (0.3.9)
+      pry (>= 0.10.4)
+    public_suffix (4.0.7)
+    puma (5.6.4)
+      nio4r (~> 2.0)
+    racc (1.6.0)
+    rack (2.2.3.1)
+    rack-test (1.1.0)
+      rack (>= 1.0, < 3)
+    rails (7.0.3)
+      actioncable (= 7.0.3)
+      actionmailbox (= 7.0.3)
+      actionmailer (= 7.0.3)
+      actionpack (= 7.0.3)
+      actiontext (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activemodel (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      bundler (>= 1.15.0)
+      railties (= 7.0.3)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.4.3)
+      loofah (~> 2.3)
+    railties (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      method_source
+      rake (>= 12.2)
+      thor (~> 1.0)
+      zeitwerk (~> 2.5)
+    rake (13.0.6)
+    regexp_parser (2.5.0)
+    rexml (3.2.5)
+    rspec-core (3.11.0)
+      rspec-support (~> 3.11.0)
+    rspec-expectations (3.11.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.11.0)
+    rspec-mocks (3.11.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.11.0)
+    rspec-rails (5.1.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      railties (>= 5.2)
+      rspec-core (~> 3.10)
+      rspec-expectations (~> 3.10)
+      rspec-mocks (~> 3.10)
+      rspec-support (~> 3.10)
+    rspec-support (3.11.0)
+    rubyzip (2.3.2)
+    sassc (2.4.0)
+      ffi (~> 1.9)
+    sassc-rails (2.1.2)
+      railties (>= 4.0.0)
+      sassc (>= 2.0)
+      sprockets (> 3.0)
+      sprockets-rails
+      tilt
+    selenium-webdriver (4.3.0)
+      childprocess (>= 0.5, < 5.0)
+      rexml (~> 3.2, >= 3.2.5)
+      rubyzip (>= 1.2.2, < 3.0)
+      websocket (~> 1.0)
+    shoulda-matchers (5.1.0)
+      activesupport (>= 5.2.0)
+    sprockets (4.0.3)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.4.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      sprockets (>= 3.0.0)
+    strscan (3.0.3)
+    thor (1.2.1)
+    tilt (2.0.10)
+    timeout (0.3.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    webdrivers (5.0.0)
+      nokogiri (~> 1.6)
+      rubyzip (>= 1.3.0)
+      selenium-webdriver (~> 4.0)
+    websocket (1.2.9)
+    websocket-driver (0.7.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
+    xpath (3.2.0)
+      nokogiri (~> 1.8)
+    zeitwerk (2.6.0)
+
+PLATFORMS
+  x86_64-darwin-20
+
+DEPENDENCIES
+  annotate
+  bcrypt
+  better_errors
+  binding_of_caller
+  byebug
+  capybara
+  pg (~> 1.1)
+  pry-rails
+  puma (~> 5.0)
+  rails (~> 7.0.3)
+  rspec-rails
+  sassc-rails
+  selenium-webdriver
+  shoulda-matchers
+  sprockets-rails
+  tzinfo-data
+  webdrivers
+
+RUBY VERSION
+   ruby 3.1.1p18
+
+BUNDLED WITH
+   2.3.14
diff --git a/rails/homeworks/capybara/README.md b/rails/homeworks/capybara/README.md
new file mode 100644
index 0000000..5206468
--- /dev/null
+++ b/rails/homeworks/capybara/README.md
@@ -0,0 +1,135 @@
+# Testing Rails With RSpec And Capybara
+
+Tonight you'll be testing the Music App that you created. You can use your code
+from that assignment or download a solution to the Music App project from the
+repo accessed through the `Download Project` button at the bottom of this page.
+(If you download the Music App solution, don't forget to create your database!)
+
+## Setup
+
+If you created the Music App with the `--minimal` flag, then Rails did not
+install Capybara / System Tests. You will want to use Capybara for this
+homework, however, so add the following gems to your __Gemfile__:
+
+```rb
+group :test do
+  gem "capybara"
+  gem "selenium-webdriver"
+  gem "webdrivers"
+end
+```
+
+Then follow the instructions in the readings for setting up RSpec-Rails, Shoulda
+Matchers, and Capybara. Hint: you'll need to add a couple more gems. (Don't
+worry about setting up FactoryBot, Faker, Spring, or Guard for this assignment;
+you'll get the chance to use those packages tomorrow.)
+
+## Model tests
+
+Run `rails g rspec:model User` to generate a spec file for the `User` model.
+
+First write some simple tests for the `User` model. Your test files should live
+in __spec/models/user_spec.rb__. Use Shoulda Matchers to test all of the user's
+validations using the following as a blueprint:
+
+```ruby
+# validations
+it { should validate_presence_of(:email) }
+```
+
+You should validate:
+
+- Presence of `email`
+- Presence of `password_digest`
+- Length of `password` > 6
+
+Refer to the Shoulda Matchers reading as needed.
+
+Next, it's time for a review of plain old RSpec! Write methods to test
+`#is_password?`, `#reset_session_token`, and `::find_by_credentials`.
+
+Make sure to run your specs (`bundle exec rspec spec/models`) and review the
+solutions for the users model before moving on.
+
+## Request tests
+
+Run `rails g rspec:request Users` to generate a spec file for the
+`UsersController`.
+
+Use the following skeleton. Fill in the pending specs to test each action in
+your `UsersController`. The first spec has been filled in for you.
+
+```ruby
+RSpec.describe "Users", type: :request do
+
+  describe "GET /users/new (#new)" do
+    it "renders the new template" do
+      get new_user_url
+      expect(response.body).to include("Sign Up!")
+    end
+  end
+
+  describe "POST /users (#create)" do
+    context "with invalid params" do
+      it "validates the presence of the user's email" do
+        # Your code here
+      end
+
+      it "validates that the password is at least 6 characters long" do
+        # Your code here
+      end
+    end
+
+    context "with valid params" do
+      it "redirects user to root page on success" do
+        # Your code here
+      end
+    end
+  end
+end
+```
+
+## System tests
+
+Finally, it's time to practice writing a system test.
+
+Your system tests should live in the __spec/system/__ folder. Run `rails g
+rspec:system Auth` to create __spec/system/auths_spec.rb__. (Feel free to change
+the name to the singular: __auth_spec.rb__.)
+
+Copy in the following skeleton and implement the pending specs to test your auth
+pattern. Once again, the first one is done for you. Refer to the Capybara
+reading as needed.
+
+**Note:** Capybara is a very picky creature. Make sure that the text on your
+labels, forms, and headers exactly matches what Capybara expects.
+
+```ruby
+RSpec.describe "Auth", type: :system do
+  before do
+    driven_by(:rack_test)
+  end
+
+  describe "the signup process" do
+    it "has a new user page" do
+      visit new_user_url
+      expect(page).to have_content "New User"
+    end
+
+    it "redirects to the root page after signup" do
+      visit new_user_url
+      fill_in "Email", with: "bill@gmail.com"
+      fill_in "Password", with: "password"
+      click_on "Sign Up"
+      # Your code here
+    end
+
+    it "re-renders the sign-up page after a failed sign-up attempt" do
+      # Your code here
+    end
+  end
+end
+```
+
+Congrats! You are well on your way to becoming a Capybara master! Make sure to
+review the solutions.
\ No newline at end of file
diff --git a/rails/homeworks/capybara/Rakefile b/rails/homeworks/capybara/Rakefile
new file mode 100644
index 0000000..d298243
--- /dev/null
+++ b/rails/homeworks/capybara/Rakefile
@@ -0,0 +1,6 @@
+# Add your own tasks in files placed in lib/tasks ending in .rake,
+# for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
+
+require_relative "config/application"
+
+Rails.application.load_tasks
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/assets/config/manifest.js b/rails/homeworks/capybara/app/assets/config/manifest.js
new file mode 100644
index 0000000..f83f92b
--- /dev/null
+++ b/rails/homeworks/capybara/app/assets/config/manifest.js
@@ -0,0 +1,2 @@
+//= link_tree ../images
+//= link_directory ../stylesheets .css
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/assets/images/.keep b/rails/homeworks/capybara/app/assets/images/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/app/assets/stylesheets/application.scss b/rails/homeworks/capybara/app/assets/stylesheets/application.scss
new file mode 100644
index 0000000..b708162
--- /dev/null
+++ b/rails/homeworks/capybara/app/assets/stylesheets/application.scss
@@ -0,0 +1,24 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS (and SCSS, if configured) file within this directory, lib/assets/stylesheets, or any plugin's
+ * vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree .
+ *= require_self
+ */
+@import url('https://fonts.googleapis.com/css?family=Raleway|Bungee+Inline');
+
+@import "reset.scss";
+@import "base.scss";
+@import "form.scss";
+@import "lists.scss";
+@import "tracks.scss";
+@import "notes.scss";
+@import "table.scss";
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/assets/stylesheets/base.scss b/rails/homeworks/capybara/app/assets/stylesheets/base.scss
new file mode 100644
index 0000000..d04e16a
--- /dev/null
+++ b/rails/homeworks/capybara/app/assets/stylesheets/base.scss
@@ -0,0 +1,105 @@
+p, a, input {
+  font-family: 'Raleway', sans-serif;
+  font-size: 18px;
+}
+
+p {
+  color: #fff;
+}
+
+a, input[type='submit'] {
+
+  &:hover {
+    transition: .5s;
+    color: white;
+  }
+}
+
+.button {
+  display: block;
+  padding: 10px;
+  border-radius: 5px;
+  border: none;
+  background-color: skyblue;
+  color: #000;
+  margin-bottom: 20px;
+
+  &:hover {
+    background-color: dodgerblue;
+    cursor: pointer;
+  }
+}
+
+input[type="submit"] {
+  padding: 10px;
+  border-radius: 5px;
+  border: none;
+  background-color: skyblue;
+  margin-bottom: 20px;
+
+  &:hover {
+    color: white;
+    background-color: dodgerblue;
+    cursor: pointer;
+  }
+}
+
+h1, h2, h3, h4 {
+  font-family: 'Bungee Inline', cursive;
+}
+
+body {
+  background-color: #111;
+}
+
+.main-content {
+  width: 800px;
+  min-height: 100vh;
+  margin: auto;
+  padding: 30px;
+  border: solid grey;
+  border-width: 0 5px;
+  background-color: #343030;
+
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+
+  .main-logo {
+    font-size: 75px;
+    margin-bottom: 30px;
+    color: #FDDB61;
+  }
+
+  nav {
+    width: 100%;
+    display: flex;
+    justify-content: space-around;
+
+    .user-detail {
+      display: flex;
+
+      p {
+        margin: 10px;
+      }
+    }
+  }
+}
+
+.page-header {
+  font-size: 40px;
+  color: #39BAAC;
+  margin-bottom: 30px;
+}
+
+.sub-header {
+  font-size: 25px;
+  color: coral;
+  margin: 20px 0;
+}
+
+.page-links {
+  display: flex;
+  justify-content: space-around;
+  width: 100%;
+}
diff --git a/rails/homeworks/capybara/app/assets/stylesheets/form.scss b/rails/homeworks/capybara/app/assets/stylesheets/form.scss
new file mode 100644
index 0000000..0a372d3
--- /dev/null
+++ b/rails/homeworks/capybara/app/assets/stylesheets/form.scss
@@ -0,0 +1,25 @@
+.form {
+  width: 400px; 
+  display: flex;
+  flex-direction: column;
+
+  p {
+    display: flex;
+    justify-content: space-between;
+    margin-bottom: 20px;
+
+    label, input {
+      display: block;
+    }
+
+    label {
+      padding-right: 10px;
+      color: white;
+    }
+  }
+
+  input[type="submit"] {
+    align-self: flex-end;
+  }
+}
+
diff --git a/rails/homeworks/capybara/app/assets/stylesheets/lists.scss b/rails/homeworks/capybara/app/assets/stylesheets/lists.scss
new file mode 100644
index 0000000..73559cb
--- /dev/null
+++ b/rails/homeworks/capybara/app/assets/stylesheets/lists.scss
@@ -0,0 +1,35 @@
+.main-list {
+
+  width: 100%;
+  display: flex;
+  flex-wrap: wrap;
+  justify-content: space-around;
+
+  li {
+    width: calc(33% - 40px);
+    height: 100px;
+    margin: 0 20px 20px 0;
+    border-radius: 10px;
+    background-color: #FDDB61;
+
+    &:hover {
+      background-color: orange;
+    }
+
+    a {
+      height: 100%;
+      width: 100%;
+      display: flex;
+      align-items: center;
+
+      p {
+        width: 100%;
+        text-align: center;
+        font-size: 25px;
+        color: black;
+      }
+    }
+  }
+}
+
+
diff --git a/rails/homeworks/capybara/app/assets/stylesheets/notes.scss b/rails/homeworks/capybara/app/assets/stylesheets/notes.scss
new file mode 100644
index 0000000..615ed0d
--- /dev/null
+++ b/rails/homeworks/capybara/app/assets/stylesheets/notes.scss
@@ -0,0 +1,18 @@
+// Place all the styles related to the Notes controller here.
+// They will automatically be included in application.css.
+// You can use Sass (SCSS) here: http://sass-lang.com/
+
+.note-item {
+
+  width: 400px;
+
+  p {
+    display: block;
+    margin-bottom: 20px;
+  }
+
+  .note-item-info {
+    display: flex;
+    justify-content: space-between;
+  }
+}
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/assets/stylesheets/reset.scss b/rails/homeworks/capybara/app/assets/stylesheets/reset.scss
new file mode 100644
index 0000000..575158f
--- /dev/null
+++ b/rails/homeworks/capybara/app/assets/stylesheets/reset.scss
@@ -0,0 +1,18 @@
+html, body, div, span, h1, h2, h3, h4, a, p, ol, ul, li, form, label, article, aside, figure, figcaption, footer, header, nav {
+  margin: 0;
+  padding: 0;
+  border: 0;
+  font-size: 100%;
+  font: inherit;
+  vertical-align: baseline;
+  text-decoration: none;
+  box-sizing: content-box;
+}
+
+ol, ul {
+  list-style: none;
+}
+
+img {
+  width: 100%
+}
diff --git a/rails/homeworks/capybara/app/assets/stylesheets/table.scss b/rails/homeworks/capybara/app/assets/stylesheets/table.scss
new file mode 100644
index 0000000..c428a90
--- /dev/null
+++ b/rails/homeworks/capybara/app/assets/stylesheets/table.scss
@@ -0,0 +1,84 @@
+.user-index {
+  width: 500px;
+  display: flex;
+  justify-content: center;
+
+  th, td {
+    display: flex;
+    justify-content: center;
+    font-size: 20px;
+    color: #39BAAC;
+	  font-family: 'Bungee Inline', cursive;
+    padding: 0px;
+
+    &:not(:first-child) {
+      width: 350px;
+      display: flex;
+      justify-content: center;
+    }
+
+    &:first-child {
+      width: 75px;
+    }
+  }
+
+  tr {
+    width: 100%;
+    height: 35px;
+    margin: 0 0px 10px 0;
+    display: flex;
+    justify-content: center;
+
+    a {
+      height: 100%;
+      width: 100%;
+      display: flex;
+      justify-content: center;
+      align-items: center;
+      border-radius: 10px;
+      background-color: #39BAAC;
+
+      
+      &:hover {
+        filter: brightness(120%);
+      }
+
+      p {
+        width: 100%;
+        text-align: center;
+        font-size: 15px;
+        color: black;
+      }
+    }
+
+    form {
+      width: 25px;
+      input[type="submit"] {
+        width: 100%;
+        height: 35px;
+        display: flex;
+        justify-content: center;
+        align-items: center;
+        font-weight: bold;
+        font-size: 20px;
+        border: 0.125rem solid transparent;
+        line-height: 10px;
+        border-radius: .5rem;
+        background: #39BAAC;
+        color: black;
+        box-shadow: 0 0.125rem 0 lightgrey;
+        padding: 0;
+        margin: 0;
+
+        &:hover {
+          filter: brightness(120%);
+        }
+
+        &:active {
+          box-shadow: 0 0 0;
+          transform: translateY(0.125rem);
+        }
+      }
+    }
+  }
+}
diff --git a/rails/homeworks/capybara/app/assets/stylesheets/tracks.scss b/rails/homeworks/capybara/app/assets/stylesheets/tracks.scss
new file mode 100644
index 0000000..c599219
--- /dev/null
+++ b/rails/homeworks/capybara/app/assets/stylesheets/tracks.scss
@@ -0,0 +1,8 @@
+// Place all the styles related to the Tracks controller here.
+// They will automatically be included in application.css.
+// You can use Sass (SCSS) here: http://sass-lang.com/
+.lyrics {
+  font-family: 'Raleway', sans-serif;
+  font-size: 20px;
+  color: white;
+}
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/controllers/albums_controller.rb b/rails/homeworks/capybara/app/controllers/albums_controller.rb
new file mode 100644
index 0000000..a4763c5
--- /dev/null
+++ b/rails/homeworks/capybara/app/controllers/albums_controller.rb
@@ -0,0 +1,51 @@
+class AlbumsController < ApplicationController
+  before_action :require_admin, only: %i(new, create, edit, update, destroy)
+  before_action :set_album, only: %i(show edit update destroy)
+  
+  def show
+  end
+
+  def new
+    @band = Band.find(params[:band_id])
+    @album = Album.new(band_id: params[:band_id])
+  end
+
+  def create
+    @album = Album.new(album_params)
+
+    if @album.save
+      redirect_to album_url(@album)
+    else
+      @band = @album.band
+      flash.now[:errors] = @album.errors.full_messages
+      render :new
+    end
+  end
+
+  def edit
+  end
+
+  def update
+    if @album.update(album_params)
+      redirect_to album_url(@album)
+    else
+      flash.now[:errors] = @album.errors.full_messages
+      render :edit
+    end
+  end
+
+  def destroy
+    @album.destroy
+    redirect_to band_url(@album.band_id)
+  end
+
+  private
+
+  def set_album
+    @album = Album.find(params[:id])
+  end
+  
+  def album_params
+    params.require(:album).permit(:band_id, :live, :title, :year)
+  end
+end
diff --git a/rails/homeworks/capybara/app/controllers/application_controller.rb b/rails/homeworks/capybara/app/controllers/application_controller.rb
new file mode 100644
index 0000000..353dcbe
--- /dev/null
+++ b/rails/homeworks/capybara/app/controllers/application_controller.rb
@@ -0,0 +1,30 @@
+class ApplicationController < ActionController::Base
+  before_action :require_logged_in
+  helper_method :current_user, :current_user_id, :logged_in?
+
+  def current_user
+    return nil unless session[:session_token]
+    @current_user ||= User.find_by(session_token: session[:session_token])
+  end
+
+  def current_user_id
+    current_user ? current_user.id : nil
+  end
+
+  def logged_in?
+    !!current_user
+  end
+
+  def login!(user)
+    @current_user = user
+    session[:session_token] = user.reset_session_token!
+  end
+
+  def require_logged_in
+    redirect_to new_session_url unless current_user
+  end
+
+  def require_admin
+    redirect_to root_url unless current_user&.admin?
+  end
+end
diff --git a/rails/homeworks/capybara/app/controllers/bands_controller.rb b/rails/homeworks/capybara/app/controllers/bands_controller.rb
new file mode 100644
index 0000000..6bd96d2
--- /dev/null
+++ b/rails/homeworks/capybara/app/controllers/bands_controller.rb
@@ -0,0 +1,53 @@
+class BandsController < ApplicationController
+  before_action :require_admin, only: %i(new, create, edit, update, destroy)
+  before_action :set_band, only: %i(show edit update destroy)
+
+  def index
+    @bands = Band.all
+  end
+
+  def show
+  end
+
+  def new
+    @band = Band.new
+  end
+
+  def create
+    @band = Band.new(band_params)
+
+    if @band.save
+      redirect_to band_url(@band)
+    else
+      flash.now[:errors] = @band.errors.full_messages
+      render :new
+    end
+  end
+
+  def edit
+  end
+
+  def update
+    if @band.update(band_params)
+      redirect_to band_url(@band)
+    else
+      flash.now[:errors] = @band.errors.full_messages
+      render :edit
+    end
+  end
+
+  def destroy
+    @band.destroy
+    redirect_to bands_url
+  end
+
+  private
+
+  def set_band
+    @band = Band.find(params[:id])
+  end
+
+  def band_params
+    params.require(:band).permit(:name)
+  end
+end
diff --git a/rails/homeworks/capybara/app/controllers/concerns/.keep b/rails/homeworks/capybara/app/controllers/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/app/controllers/notes_controller.rb b/rails/homeworks/capybara/app/controllers/notes_controller.rb
new file mode 100644
index 0000000..d89a94d
--- /dev/null
+++ b/rails/homeworks/capybara/app/controllers/notes_controller.rb
@@ -0,0 +1,21 @@
+class NotesController < ApplicationController
+  def create
+    note = current_user.notes.new(note_params)
+    note.save
+    flash[:errors] = note.errors.full_messages
+    redirect_to track_url(note.track_id)
+  end
+
+  def destroy
+    # note = current_user.notes.find(params[:id])
+    note = Note.find(params[:id])
+    note.destroy if current_user.admin? || note.author == current_user
+    redirect_to track_url(note.track_id)
+  end
+
+  private
+  
+  def note_params
+    params.require(:note).permit(:content, :track_id)
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/controllers/sessions_controller.rb b/rails/homeworks/capybara/app/controllers/sessions_controller.rb
new file mode 100644
index 0000000..09b42f3
--- /dev/null
+++ b/rails/homeworks/capybara/app/controllers/sessions_controller.rb
@@ -0,0 +1,34 @@
+class SessionsController < ApplicationController
+  skip_before_action :require_logged_in, only: %i(new create)
+  
+  def new
+  end
+
+  def create
+    user = User.find_by_credentials(
+      params[:user][:email],
+      params[:user][:password]
+    )
+
+    if user.nil?
+      flash.now[:errors] = ["Invalid credentials."]
+      render :new
+
+    # Notice you have User#activated? even though you didn't define it!
+    # Rails gives you this method for free because it matches a column name.
+    elsif !user.activated?
+      flash.now[:errors] = ['You must activate your account first! Check your email.']
+      render :new
+    else
+      login!(user)
+      redirect_to root_url
+    end
+  end
+
+  def destroy
+    current_user.try(:reset_session_token!)
+    session[:session_token] = nil
+
+    redirect_to new_session_url
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/controllers/tracks_controller.rb b/rails/homeworks/capybara/app/controllers/tracks_controller.rb
new file mode 100644
index 0000000..ce40c48
--- /dev/null
+++ b/rails/homeworks/capybara/app/controllers/tracks_controller.rb
@@ -0,0 +1,51 @@
+class TracksController < ApplicationController
+  before_action :require_admin, only: %i(new, create, edit, update, destroy)
+  before_action :set_track, only: %i(show edit update destroy)
+
+  def show
+  end
+
+  def new
+    @album = Album.find(params[:album_id])
+    @track = Track.new(album_id: params[:album_id])
+  end
+
+  def create
+    @track = Track.new(track_params)
+
+    if @track.save
+      redirect_to track_url(@track)
+    else
+      @album = @track.album
+      flash.now[:errors] = @track.errors.full_messages
+      render :new
+    end
+  end
+
+  def edit
+  end
+
+  def update
+    if @track.update(track_params)
+      redirect_to track_url(@track)
+    else
+      flash.now[:errors] = @track.errors.full_messages
+      render :edit
+    end
+  end
+
+  def destroy
+    @track.destroy
+    redirect_to album_url(@track.album_id)
+  end
+
+  private
+
+  def set_track
+    @track = Track.find(params[:id])
+  end
+
+  def track_params
+    params.require(:track).permit(:album_id, :bonus, :lyrics, :title, :ord)
+  end
+end
diff --git a/rails/homeworks/capybara/app/controllers/users_controller.rb b/rails/homeworks/capybara/app/controllers/users_controller.rb
new file mode 100644
index 0000000..6eb7627
--- /dev/null
+++ b/rails/homeworks/capybara/app/controllers/users_controller.rb
@@ -0,0 +1,58 @@
+class UsersController < ApplicationController
+  skip_before_action :require_logged_in, except: %i(show)
+  before_action :require_admin, only: %i(index toggle_admin)
+
+  def index
+    @users = User.order(:email)
+  end
+
+  def show
+  end
+
+  def new
+    @user = User.new
+  end
+
+  def create
+    @user = User.new(user_params)
+
+    if @user.save
+      # Uncomment these lines to enable the email activation flow
+      #-------------------------------------------------------------------------
+      # UserMailer.activation_email(@user).deliver_now
+      # flash[:notice] = 'Successfully created your account! Check your inbox for an activation email.'
+      # redirect_to new_session_url
+      #-------------------------------------------------------------------------
+
+      # And remove these lines
+      #---------------------
+      @user.activate!
+      login!(@user)
+      redirect_to root_url
+      #---------------------
+    else
+      flash.now[:errors] = @user.errors.full_messages
+      render :new
+    end
+  end
+
+  def activate
+    @user = User.find_by(activation_token: params[:activation_token])
+    @user.activate!
+    login!(@user)
+    flash[:notice] = 'Successfully activated your account!'
+    redirect_to root_url
+  end
+
+  def toggle_admin
+    @user = User.find(params[:id])
+    @user.toggle_admin!
+    redirect_to users_url
+  end
+
+  private
+
+  def user_params
+    params.require(:user).permit(:email, :password)
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/helpers/application_helper.rb b/rails/homeworks/capybara/app/helpers/application_helper.rb
new file mode 100644
index 0000000..23df6e0
--- /dev/null
+++ b/rails/homeworks/capybara/app/helpers/application_helper.rb
@@ -0,0 +1,10 @@
+module ApplicationHelper
+  def ugly_lyrics(lyrics)
+    formatted_lyrics = ""
+    lyrics.lines.each do |line|
+      formatted_lyrics << "&#9835; #{h(line)}"
+    end
+
+    "<pre class='lyrics'>#{formatted_lyrics}</pre>".html_safe
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/mailers/application_mailer.rb b/rails/homeworks/capybara/app/mailers/application_mailer.rb
new file mode 100644
index 0000000..286b223
--- /dev/null
+++ b/rails/homeworks/capybara/app/mailers/application_mailer.rb
@@ -0,0 +1,4 @@
+class ApplicationMailer < ActionMailer::Base
+  default from: 'from@example.com'
+  layout 'mailer'
+end
diff --git a/rails/homeworks/capybara/app/mailers/user_mailer.rb b/rails/homeworks/capybara/app/mailers/user_mailer.rb
new file mode 100644
index 0000000..b655b2e
--- /dev/null
+++ b/rails/homeworks/capybara/app/mailers/user_mailer.rb
@@ -0,0 +1,6 @@
+class UserMailer < ApplicationMailer
+  def activation_email(user)
+    @user = user
+    mail(to: user.email, subject: "Welcome to Music App! Please activate your account.")
+  end
+end
diff --git a/rails/homeworks/capybara/app/models/album.rb b/rails/homeworks/capybara/app/models/album.rb
new file mode 100644
index 0000000..88e8012
--- /dev/null
+++ b/rails/homeworks/capybara/app/models/album.rb
@@ -0,0 +1,28 @@
+# == Schema Information
+#
+# Table name: albums
+#
+#  id         :bigint           not null, primary key
+#  title      :string           not null
+#  band_id    :bigint           not null
+#  year       :integer          not null
+#  live       :boolean          default(FALSE), not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+class Album < ApplicationRecord
+  validates :band, :title, :year, presence: true
+  # can't use presence validation with boolean field
+  validates :live, inclusion: { in: [true, false] }
+  validates :title, uniqueness: { scope: :band_id }
+  validates :year, numericality: { minimum: 1900, maximum: 9000 }
+
+  after_initialize :set_defaults
+
+  belongs_to :band
+  has_many :tracks, dependent: :destroy
+
+  def set_defaults
+    self.live ||= false
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/models/application_record.rb b/rails/homeworks/capybara/app/models/application_record.rb
new file mode 100644
index 0000000..b63caeb
--- /dev/null
+++ b/rails/homeworks/capybara/app/models/application_record.rb
@@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+  primary_abstract_class
+end
diff --git a/rails/homeworks/capybara/app/models/band.rb b/rails/homeworks/capybara/app/models/band.rb
new file mode 100644
index 0000000..6b06884
--- /dev/null
+++ b/rails/homeworks/capybara/app/models/band.rb
@@ -0,0 +1,15 @@
+# == Schema Information
+#
+# Table name: bands
+#
+#  id         :bigint           not null, primary key
+#  name       :string           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+class Band < ApplicationRecord
+  validates :name, presence: true, uniqueness: true
+
+  has_many :albums, dependent: :destroy
+  has_many :tracks, through: :albums
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/models/concerns/.keep b/rails/homeworks/capybara/app/models/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/app/models/note.rb b/rails/homeworks/capybara/app/models/note.rb
new file mode 100644
index 0000000..3712c14
--- /dev/null
+++ b/rails/homeworks/capybara/app/models/note.rb
@@ -0,0 +1,17 @@
+# == Schema Information
+#
+# Table name: notes
+#
+#  id         :bigint           not null, primary key
+#  track_id   :bigint           not null
+#  author_id  :bigint           not null
+#  content    :text             not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+class Note < ApplicationRecord
+  validates :content, presence: true
+  
+  belongs_to :track
+  belongs_to :author, class_name: :User
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/models/track.rb b/rails/homeworks/capybara/app/models/track.rb
new file mode 100644
index 0000000..840762e
--- /dev/null
+++ b/rails/homeworks/capybara/app/models/track.rb
@@ -0,0 +1,34 @@
+# == Schema Information
+#
+# Table name: tracks
+#
+#  id         :bigint           not null, primary key
+#  title      :string           not null
+#  album_id   :bigint           not null
+#  ord        :integer          not null
+#  bonus      :boolean          default(FALSE), not null
+#  lyrics     :text
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+class Track < ApplicationRecord
+  validates :title, :ord, presence: true
+  # can't use presence validation with boolean field
+  validates :bonus, inclusion: { in: [true, false] }
+  validates :ord, uniqueness: { scope: :album_id }
+
+  belongs_to :album
+
+  has_one :band,
+    through: :album,
+    source: :band
+
+  has_many :notes,
+    dependent: :destroy
+
+  after_initialize :set_defaults
+
+  def set_defaults
+    self.bonus ||= false
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/models/user.rb b/rails/homeworks/capybara/app/models/user.rb
new file mode 100644
index 0000000..8bd0696
--- /dev/null
+++ b/rails/homeworks/capybara/app/models/user.rb
@@ -0,0 +1,96 @@
+# == Schema Information
+#
+# Table name: users
+#
+#  id               :bigint           not null, primary key
+#  email            :string           not null
+#  password_digest  :string           not null
+#  session_token    :string           not null
+#  created_at       :datetime         not null
+#  updated_at       :datetime         not null
+#  activated        :boolean          default(FALSE), not null
+#  activation_token :string           not null
+#  admin            :boolean          default(FALSE), not null
+#
+class User < ApplicationRecord
+  validates :activation_token, :email, :session_token, uniqueness: true
+  validates :password, length: { minimum: 6, allow_nil: true }
+  # can't use presence validation with boolean field
+  validates :activated, :admin, inclusion: { in: [true, false] }
+  validates :email,
+            :password_digest,
+            :session_token,
+            :activation_token,
+            presence: true
+
+  attr_reader :password
+
+  before_validation :ensure_session_token
+  after_initialize :set_activation_token, :set_defaults
+
+  has_many :notes, foreign_key: :author_id, dependent: :destroy, inverse_of: :author
+
+  def self.find_by_credentials(email, password)
+    user = User.find_by(email: email)
+    # `user&.is_password?(password)` is syntactic sugar for
+    # `user && user.is_password?(password)`
+    user&.is_password?(password) ? user : nil
+  end
+
+  def password=(password)
+    @password = password
+    self.password_digest = BCrypt::Password.create(password)
+  end
+
+  def is_password?(password)
+    BCrypt::Password.new(self.password_digest).is_password?(password)
+  end
+
+  def reset_session_token!
+    self.session_token = generate_unique_session_token
+    self.save!
+    self.session_token
+  end
+
+  def activate!
+    self.toggle!(:activated) unless self.activated?
+  end
+
+  def toggle_admin!
+    self.toggle!(:admin)
+  end
+  
+  private
+
+  def generate_unique_session_token
+    # `SecureRandom::urlsafe_base64` does not guarantee uniqueness. Wrapping
+    # this call in a loop ensures that no other user has the generated token.
+    loop do
+      session_token = SecureRandom::urlsafe_base64(16)
+      return session_token unless User.exists?(session_token: session_token)
+    end
+  end
+
+  def ensure_session_token
+    self.session_token ||= generate_unique_session_token
+  end
+
+  ##
+  # This method is for the mailer!
+  ##
+  def generate_unique_activation_token
+    loop do
+      token = SecureRandom::urlsafe_base64(16)
+      return token unless self.class.exists?(activation_token: token)
+    end
+  end
+
+  def set_activation_token
+    self.activation_token ||= generate_unique_activation_token
+  end
+
+  def set_defaults
+    self.activated ||= false
+    self.admin ||= false
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/views/albums/_form.html.erb b/rails/homeworks/capybara/app/views/albums/_form.html.erb
new file mode 100644
index 0000000..b6d9185
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/albums/_form.html.erb
@@ -0,0 +1,53 @@
+<% action_url = album.persisted? ? album_url(album) : albums_url %>
+<% http_method = album.persisted? ? "PATCH" : "POST" %>
+<% button_text = album.persisted? ? "Update Album!" : "Create Album!" %>
+
+<form class='form' action="<%= action_url %>" method="POST">
+  <input type="hidden" name="_method" value="<%= http_method %>">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>">
+
+  <p>
+    <label for='album-title'>Title</label>
+    <input id='album-title' type="text" name="album[title]" value="<%= album.title %>">
+  </p>
+
+  <p>
+    <label for='album-band'>Band</label>
+    <select id='album-band' name="album[band_id]">
+        <% Band.all.each do |band| %>
+            <option
+                <%= "selected" if album.band_id == band.id %>
+                value="<%= band.id %>">
+                <%= band.name %>
+            </option>
+        <% end %>
+    </select>
+  </p>
+
+  <p>
+    <label for="album_live_t">Live</label>
+    <input
+      type="radio"
+      name="album[live]"
+      value="t"
+      id="album_live_t"
+      <%= "checked" if album.live %>>
+    <label for="album_live_f">Studio</label>
+    <input
+      type="radio"
+      name="album[live]"
+      value="f"
+      id="album_live_f"
+      <%= "checked" if !album.live %>>
+  </p>
+
+  <p>
+    <label for='album-year'>Year</label>
+    <input id='album-year' type="number" name="album[year]" value="<%= album.year %>">
+  </p>
+
+  <input type="submit" value="<%= button_text %>">
+</form>
diff --git a/rails/homeworks/capybara/app/views/albums/edit.html.erb b/rails/homeworks/capybara/app/views/albums/edit.html.erb
new file mode 100644
index 0000000..cf2fc9e
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/albums/edit.html.erb
@@ -0,0 +1,3 @@
+<h1 class='page-header'>Edit <%= @album.title %></h1>
+
+<%= render "form", album: @album %>
diff --git a/rails/homeworks/capybara/app/views/albums/new.html.erb b/rails/homeworks/capybara/app/views/albums/new.html.erb
new file mode 100644
index 0000000..47e6b87
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/albums/new.html.erb
@@ -0,0 +1,3 @@
+<h1 class='page-header'>New <%= @band.name %> Album!</h1>
+
+<%= render "form", album: @album %>
diff --git a/rails/homeworks/capybara/app/views/albums/show.html.erb b/rails/homeworks/capybara/app/views/albums/show.html.erb
new file mode 100644
index 0000000..6ef7494
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/albums/show.html.erb
@@ -0,0 +1,28 @@
+<h1 class='page-header'><%= @album.title %></h1>
+
+<% if @album.tracks.length > 0 %>
+<ul class='main-list'>
+  <% @album.tracks.each do |track| %>
+    <li><a href="<%= track_url(track) %>"><p><%= track.title %></p></a></li>
+  <% end %>
+</ul>
+<% else %>
+  <p>This album has no tracks... yet!</p> 
+<% end %>
+
+<h4 class='sub-header'>Links</h4>
+<ul class='page-links'>
+  <% if current_user.admin? %>
+    <li><a class='button' href="<%= new_album_track_url(@album) %>">New track</a></li>
+    <li><a class='button' href="<%= edit_album_url(@album) %>">Edit album</a></li>
+    <li>
+      <form action="<%= album_url(@album) %>" method="POST">
+        <input type="hidden" name="_method" value="DELETE">
+        <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>" >
+        <input type="submit" value="Destroy Album">
+      </form>
+    </li>
+    <li><a class='button' href="<%= users_url %>">Users</a></li>
+  <% end %>
+  <li><a class='button' href="<%= band_url(@album.band) %>">Back to <%= @album.band.name %></a></li>
+</ul>
diff --git a/rails/homeworks/capybara/app/views/bands/_form.html.erb b/rails/homeworks/capybara/app/views/bands/_form.html.erb
new file mode 100644
index 0000000..c520153
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/bands/_form.html.erb
@@ -0,0 +1,17 @@
+<% action_url = band.persisted? ? band_url(band) : bands_url %>
+<% http_method = band.persisted? ? "PATCH" : "POST" %>
+
+<form class='form' action="<%= action_url %>" method="POST">
+  <input type="hidden" name="_method" value="<%= http_method %>">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>">
+
+  <p>
+    <label for='band-name'>Name</label>
+    <input id='band-name' type="text" name="band[name]" value="<%= band.name %>">
+  </p>
+
+  <input type="submit" value="Create Band!">
+</form>
diff --git a/rails/homeworks/capybara/app/views/bands/edit.html.erb b/rails/homeworks/capybara/app/views/bands/edit.html.erb
new file mode 100644
index 0000000..759021d
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/bands/edit.html.erb
@@ -0,0 +1,3 @@
+<h1 class='page-header'>Edit <%= @band.name %></h1>
+
+<%= render "form", band: @band %>
diff --git a/rails/homeworks/capybara/app/views/bands/index.html.erb b/rails/homeworks/capybara/app/views/bands/index.html.erb
new file mode 100644
index 0000000..5468c79
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/bands/index.html.erb
@@ -0,0 +1,15 @@
+<h1 class='page-header'>Bands</h1>
+
+<ul class='main-list'>
+  <% @bands.each do |band| %>
+    <li><a href="<%= band_url(band) %>"><p><%= band.name %></p></a></li>
+  <% end %>
+</ul>
+
+<% if current_user.admin? %>
+  <h4 class='sub-header'>Links</h4>
+  <ul class='page-links'>
+    <li><a class='button' href="<%= new_band_url %>" >New band</a></li>
+    <li><a class='button' href="<%= users_url %>">Users</a></li>  
+  </ul>
+<% end %>
diff --git a/rails/homeworks/capybara/app/views/bands/new.html.erb b/rails/homeworks/capybara/app/views/bands/new.html.erb
new file mode 100644
index 0000000..31e9173
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/bands/new.html.erb
@@ -0,0 +1,3 @@
+<h1 class='page-header'>New Band!</h1>
+
+<%= render "form", band: @band %>
diff --git a/rails/homeworks/capybara/app/views/bands/show.html.erb b/rails/homeworks/capybara/app/views/bands/show.html.erb
new file mode 100644
index 0000000..e359ef8
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/bands/show.html.erb
@@ -0,0 +1,30 @@
+<h1 class='page-header'><%= @band.name %></h1>
+
+<h4 class='sub-header'>Albums</h4>
+
+<% if @band.albums.length > 0 %>
+  <ul class='main-list'>
+  <% @band.albums.each do |album| %>
+    <li><a href="<%= album_url(album) %>"><p><%= album.title %></p></a></li>
+  <% end %>
+  </ul>
+<% else %>
+  <p>This band has no albums... yet!</p>
+<% end %>
+
+<h4 class='sub-header'>Links</h4>
+<ul class='page-links'>
+  <% if current_user.admin? %>
+    <li><a class='button' href="<%= new_band_album_url(@band) %>">New album</a></li>
+    <li><a class='button' href="<%= edit_band_url(@band) %>">Edit Band</a></li>
+    <li>
+      <form action="<%= band_url(@band) %>" method="POST">
+        <input type="hidden" name="_method" value="DELETE">
+        <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>" >
+        <input type="submit" value="Destroy Band">
+      </form>
+    </li>
+    <li><a class='button' href="<%= users_url %>">Users</a></li>
+  <% end %>
+  <li><a class='button' href="<%= bands_url %>">All bands</a></li>
+</ul>
diff --git a/rails/homeworks/capybara/app/views/layouts/application.html.erb b/rails/homeworks/capybara/app/views/layouts/application.html.erb
new file mode 100644
index 0000000..9504b4f
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/layouts/application.html.erb
@@ -0,0 +1,48 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>Music App</title>
+    <meta name="viewport" content="width=device-width,initial-scale=1">
+    <%= csrf_meta_tags %>
+    <%= csp_meta_tag %>
+
+    <%= stylesheet_link_tag "application" %>
+  </head>
+
+  <body>
+    <div class='main-content'>
+      <h1 class='main-logo'>Music App</h1>
+      <% if logged_in? %>
+        <nav>
+          <a class='button' href="<%= bands_url %>">Take me Home</a>
+          
+          <div class='user-detail'>
+            <p>Logged in as: <%= current_user.email %></p>
+          <form action=<%= session_url %> method='post'>
+            <input
+              type="hidden"
+              name="_method"
+              value="delete">
+            <input
+              type="hidden"
+              name="authenticity_token"
+              value="<%= form_authenticity_token %>">
+            <input 
+              type="submit" value="Sign Out">
+          </form>
+          </div>
+        </nav>
+      <% end %>
+
+      <% if flash[:notice] %>
+        <p><%= flash[:notice] %></p>
+      <% end %>
+
+      <% if flash[:errors] %>
+        <p><%= flash[:errors].join(", ") %></p>
+      <% end %>
+
+      <%= yield %>
+    </div>
+  </body>
+</html>
diff --git a/rails/homeworks/capybara/app/views/layouts/mailer.html.erb b/rails/homeworks/capybara/app/views/layouts/mailer.html.erb
new file mode 100644
index 0000000..d062c6b
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/layouts/mailer.html.erb
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
+    <style>
+      /* Email styles need to be inline */
+    </style>
+  </head>
+
+  <body>
+    <%= yield %>
+  </body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/capybara/app/views/layouts/mailer.text.erb b/rails/homeworks/capybara/app/views/layouts/mailer.text.erb
new file mode 100644
index 0000000..37f0bdd
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/layouts/mailer.text.erb
@@ -0,0 +1 @@
+<%= yield %>
diff --git a/rails/homeworks/capybara/app/views/note/_form.html.erb b/rails/homeworks/capybara/app/views/note/_form.html.erb
new file mode 100644
index 0000000..eaa8d98
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/note/_form.html.erb
@@ -0,0 +1,19 @@
+<h4 class='sub-header'>New Note</h4>
+
+<form class='form' action="<%= notes_url %>" method="POST">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>">
+
+  <input type="hidden" name="note[track_id]" value="<%= track.id %>">
+
+  <p>
+    <label for="note_content">Content</label>
+    <textarea id="note_content"
+      rows="7" cols="30"
+      name="note[content]"></textarea>
+  </p>
+
+  <input type="submit" value="Create Note">
+</form>
diff --git a/rails/homeworks/capybara/app/views/note/_note.html.erb b/rails/homeworks/capybara/app/views/note/_note.html.erb
new file mode 100644
index 0000000..a7ddc5b
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/note/_note.html.erb
@@ -0,0 +1,14 @@
+<div class='note-item'>
+  <p><%= note.content %></p>
+  <div class='note-item-info'>
+    <p>Authored by: <%= note.author.email %></p>
+
+    <% if note.author == current_user || current_user.admin? %>
+      <form action="<%= note_url(note) %>" method="POST">
+        <input type="hidden" name="_method" value="DELETE">
+        <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>" >
+        <input type="submit" value="Destroy Note">
+      </form>
+    <% end %>
+  </div>
+</div>
diff --git a/rails/homeworks/capybara/app/views/sessions/new.html.erb b/rails/homeworks/capybara/app/views/sessions/new.html.erb
new file mode 100644
index 0000000..6c2ba0e
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/sessions/new.html.erb
@@ -0,0 +1,22 @@
+<h2 class='page-header'>Sign In</h2>
+
+<a class='button' href=<%= new_user_url %> >Go to Sign Up!</a>
+
+<form class='form' action="<%= session_url %>" method="post">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>">
+
+  <p>
+    <label for='new-user-email'>Email</label>
+    <input id='new-user-email' type="text" name="user[email]">
+  </p>
+
+  <p>
+    <label for='new-user-password'>Password</label>
+    <input id='new-user-password' type="password" name="user[password]">
+  </p>
+
+  <input type="submit" value="Sign In!">
+</form>
diff --git a/rails/homeworks/capybara/app/views/tracks/_form.html.erb b/rails/homeworks/capybara/app/views/tracks/_form.html.erb
new file mode 100644
index 0000000..ab8a9da
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/tracks/_form.html.erb
@@ -0,0 +1,61 @@
+<% action_url = track.persisted? ? track_url(track) : tracks_url %>
+<% http_method = track.persisted? ? "PATCH" : "POST" %>
+
+
+<form class='form' action="<%= action_url %>" method="POST" %>
+  <input type="hidden" name="_method" value="<%= http_method %>">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>">
+
+<p>
+  <label for='track-title'>Title</label>
+  <input id='track-title' type="text" name="track[title]" value="<%= track.title %>">
+</p>
+
+<p>
+<label for='track-album'>Album</label>
+  <select id='track-album' name="track[album_id]">
+    <% Album.all.each do |album| %>
+      <option
+        <%= "selected" if track.album_id == album.id %>
+        value="<%= album.id %>">
+        <%= album.title %>
+      </option>
+    <% end %>
+  </select>
+</p>
+
+<p>
+  <label for='track-ord'>Ord</label>
+  <input id='track-ord' type="number" name="track[ord]" value="<%= track.ord %>">
+</p>
+
+<p>
+  <label for="track_bonus_f">Standard</label>
+  <input
+    type="radio"
+    name="track[bonus]"
+    value="f"
+    id="track_bonus_f"
+    <%= "checked" if !track.bonus %>>
+  <br>
+  <label for="track_bonus_t">Bonus</label>
+  <input
+    type="radio"
+    name="track[bonus]"
+    value="t"
+    id="track_bonus_t"
+    <%= "checked" if track.bonus %>>
+</p>
+
+<p>
+  <label for="track_lyrics">Lyrics</label><br>
+  <textarea id="track_lyrics"
+    rows="10" cols="40"
+    name="track[lyrics]"><%= track.lyrics %></textarea>
+</p>
+
+  <input type="submit" value="Create Track">
+</form>
diff --git a/rails/homeworks/capybara/app/views/tracks/edit.html.erb b/rails/homeworks/capybara/app/views/tracks/edit.html.erb
new file mode 100644
index 0000000..6aecefa
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/tracks/edit.html.erb
@@ -0,0 +1,3 @@
+<h1 class='page-header'>Edit <%= @track.title %></h1>
+
+<%= render "form", track: @track %>
diff --git a/rails/homeworks/capybara/app/views/tracks/new.html.erb b/rails/homeworks/capybara/app/views/tracks/new.html.erb
new file mode 100644
index 0000000..b1afe0d
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/tracks/new.html.erb
@@ -0,0 +1,3 @@
+<h1 class='page-header'>New <%= @album.title %> Track</h1>
+
+<%= render "form", track: @track %>
diff --git a/rails/homeworks/capybara/app/views/tracks/show.html.erb b/rails/homeworks/capybara/app/views/tracks/show.html.erb
new file mode 100644
index 0000000..26fc333
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/tracks/show.html.erb
@@ -0,0 +1,27 @@
+<h1 class='page-header'><%= @track.title %></h1>
+
+<%= ugly_lyrics(@track.lyrics) %>
+
+<%= render "note/form", track: @track %>
+
+<h4 class='sub-header'>Notes</h4>
+
+<% @track.notes.each do |note| %>
+  <%= render "note/note", note: note %>
+<% end %>
+
+<h4 class='sub-header'>Links</h4>
+<ul class='page-links'>
+  <% if current_user.admin? %>
+    <li><a class='button' href="<%= edit_track_url(@track) %>">Edit Track</a></li>
+    <li>
+      <form action="<%= track_url(@track) %>" method="POST">
+        <input type="hidden" name="_method" value="DELETE">
+        <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>" >
+        <input type="submit" value="Destroy Track">
+      </form>
+    </li>
+    <li><a class='button' href="<%= users_url %>">Users</a></li>
+  <% end %>
+  <li><a class='button' href="<%= album_url(@track.album) %>"><%= @track.album.title %></a></li>
+</ul>
diff --git a/rails/homeworks/capybara/app/views/user_mailer/activation_email.html.erb b/rails/homeworks/capybara/app/views/user_mailer/activation_email.html.erb
new file mode 100644
index 0000000..a38ad7f
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/user_mailer/activation_email.html.erb
@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta content='text/html; charset=UTF-8' http-equiv='Content-Type' />
+  </head>
+  <body>
+    <h1>Welcome <%= @user.email %>, </h1>
+    <p>
+      You have successfully signed up to my app!
+      Please activate your account by visiting this link:
+      <a href="<%= activate_users_url(activation_token: @user.activation_token) %>">Activate</a>
+    </p>
+
+    <p>
+      If you can't click the link, copy and paste this URL into your browser:
+      <%= activate_users_url(activation_token: @user.activation_token) %>
+    </p>
+
+    <p>
+      Thanks for joining and have a great day!
+    </p>
+  </body>
+</html>
diff --git a/rails/homeworks/capybara/app/views/user_mailer/activation_email.text.erb b/rails/homeworks/capybara/app/views/user_mailer/activation_email.text.erb
new file mode 100644
index 0000000..93fa773
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/user_mailer/activation_email.text.erb
@@ -0,0 +1,9 @@
+Welcome to my app <%= @user.email %>!
+===============================================
+
+You have successfully signed up to my app!
+Please activate your account by visiting this link:
+
+<%= activate_users_url(activation_token: @user.activation_token) %>
+
+Thanks for joining and have a great day!
diff --git a/rails/homeworks/capybara/app/views/users/index.html.erb b/rails/homeworks/capybara/app/views/users/index.html.erb
new file mode 100644
index 0000000..ca635b0
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/users/index.html.erb
@@ -0,0 +1,22 @@
+<h1 class='page-header'>Users</h1>
+<% if current_user.admin? %>
+  <table class='user-index'>
+    <tr>
+      <th> Admin? </th>
+      <th> Email </th>
+    </tr>
+    <% @users.each do |user| %>
+      <tr>
+        <td>
+          <form action="<%= toggle_admin_user_url(user) %>" method="POST">
+            <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>" >
+            <input type="submit" value="<%= user.admin? ? "✔" : " " %>">
+          </form>
+        </td>
+        <td>
+          <a href="<%= user_url(user) %>"><p><%= user.email %></p></a>
+        </td>
+      </tr>
+    <% end %>
+  </ul>
+<% end %>
diff --git a/rails/homeworks/capybara/app/views/users/new.html.erb b/rails/homeworks/capybara/app/views/users/new.html.erb
new file mode 100644
index 0000000..cab23b2
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/users/new.html.erb
@@ -0,0 +1,22 @@
+<h1 class='page-header'>New User</h1>
+
+<a class='button' href=<%= new_session_url %> >Go to Sign In!</a>
+
+<form class='form' action="<%= users_url %>" method="post">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>">
+
+  <p>
+    <label for='new-user-email'>Email</label>
+    <input id='new-user-email' type="text" name="user[email]">
+  </p>
+
+  <p>
+    <label for='new-user-password'>Password</label>
+    <input id='new-user-password' type="password" name="user[password]">
+  </p>
+
+  <input type="submit" value="Sign Up!">
+</form>
diff --git a/rails/homeworks/capybara/app/views/users/show.html.erb b/rails/homeworks/capybara/app/views/users/show.html.erb
new file mode 100644
index 0000000..86cdc24
--- /dev/null
+++ b/rails/homeworks/capybara/app/views/users/show.html.erb
@@ -0,0 +1,4 @@
+<h1 class='page-header'>User Profile</h1>
+<p>
+  Email: <%= current_user.email %>
+</p>
diff --git a/rails/homeworks/capybara/bin/bundle b/rails/homeworks/capybara/bin/bundle
new file mode 100644
index 0000000..2060668
--- /dev/null
+++ b/rails/homeworks/capybara/bin/bundle
@@ -0,0 +1,114 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'bundle' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "rubygems"
+
+m = Module.new do
+  module_function
+
+  def invoked_as_script?
+    File.expand_path($0) == File.expand_path(__FILE__)
+  end
+
+  def env_var_version
+    ENV["BUNDLER_VERSION"]
+  end
+
+  def cli_arg_version
+    return unless invoked_as_script? # don't want to hijack other binstubs
+    return unless "update".start_with?(ARGV.first || " ") # must be running `bundle update`
+    bundler_version = nil
+    update_index = nil
+    ARGV.each_with_index do |a, i|
+      if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
+        bundler_version = a
+      end
+      next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
+      bundler_version = $1
+      update_index = i
+    end
+    bundler_version
+  end
+
+  def gemfile
+    gemfile = ENV["BUNDLE_GEMFILE"]
+    return gemfile if gemfile && !gemfile.empty?
+
+    File.expand_path("../Gemfile", __dir__)
+  end
+
+  def lockfile
+    lockfile =
+      case File.basename(gemfile)
+      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
+      else "#{gemfile}.lock"
+      end
+    File.expand_path(lockfile)
+  end
+
+  def lockfile_version
+    return unless File.file?(lockfile)
+    lockfile_contents = File.read(lockfile)
+    return unless lockfile_contents =~ /\n\nBUNDLED WITH\n\s{2,}(#{Gem::Version::VERSION_PATTERN})\n/
+    Regexp.last_match(1)
+  end
+
+  def bundler_requirement
+    @bundler_requirement ||=
+      env_var_version || cli_arg_version ||
+        bundler_requirement_for(lockfile_version)
+  end
+
+  def bundler_requirement_for(version)
+    return "#{Gem::Requirement.default}.a" unless version
+
+    bundler_gem_version = Gem::Version.new(version)
+
+    requirement = bundler_gem_version.approximate_recommendation
+
+    return requirement unless Gem.rubygems_version < Gem::Version.new("2.7.0")
+
+    requirement += ".a" if bundler_gem_version.prerelease?
+
+    requirement
+  end
+
+  def load_bundler!
+    ENV["BUNDLE_GEMFILE"] ||= gemfile
+
+    activate_bundler
+  end
+
+  def activate_bundler
+    gem_error = activation_error_handling do
+      gem "bundler", bundler_requirement
+    end
+    return if gem_error.nil?
+    require_error = activation_error_handling do
+      require "bundler/version"
+    end
+    return if require_error.nil? && Gem::Requirement.new(bundler_requirement).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+    warn "Activating bundler (#{bundler_requirement}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_requirement}'`"
+    exit 42
+  end
+
+  def activation_error_handling
+    yield
+    nil
+  rescue StandardError, LoadError => e
+    e
+  end
+end
+
+m.load_bundler!
+
+if m.invoked_as_script?
+  load Gem.bin_path("bundler", "bundle")
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/bin/rails b/rails/homeworks/capybara/bin/rails
new file mode 100644
index 0000000..fa3c01a
--- /dev/null
+++ b/rails/homeworks/capybara/bin/rails
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+APP_PATH = File.expand_path("../config/application", __dir__)
+require_relative "../config/boot"
+require "rails/commands"
\ No newline at end of file
diff --git a/rails/homeworks/capybara/bin/rake b/rails/homeworks/capybara/bin/rake
new file mode 100644
index 0000000..19d605d
--- /dev/null
+++ b/rails/homeworks/capybara/bin/rake
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+require_relative "../config/boot"
+require "rake"
+Rake.application.run
\ No newline at end of file
diff --git a/rails/homeworks/capybara/bin/setup b/rails/homeworks/capybara/bin/setup
new file mode 100644
index 0000000..9bd670f
--- /dev/null
+++ b/rails/homeworks/capybara/bin/setup
@@ -0,0 +1,33 @@
+#!/usr/bin/env ruby
+require "fileutils"
+
+# path to your application root.
+APP_ROOT = File.expand_path("..", __dir__)
+
+def system!(*args)
+  system(*args) || abort("\n== Command #{args} failed ==")
+end
+
+FileUtils.chdir APP_ROOT do
+  # This script is a way to set up or update your development environment automatically.
+  # This script is idempotent, so that you can run it at any time and get an expectable outcome.
+  # Add necessary setup steps to this file.
+
+  puts "== Installing dependencies =="
+  system! "gem install bundler --conservative"
+  system("bundle check") || system!("bundle install")
+
+  # puts "\n== Copying sample files =="
+  # unless File.exist?("config/database.yml")
+  #   FileUtils.cp "config/database.yml.sample", "config/database.yml"
+  # end
+
+  puts "\n== Preparing database =="
+  system! "bin/rails db:prepare"
+
+  puts "\n== Removing old logs and tempfiles =="
+  system! "bin/rails log:clear tmp:clear"
+
+  puts "\n== Restarting application server =="
+  system! "bin/rails restart"
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config.ru b/rails/homeworks/capybara/config.ru
new file mode 100644
index 0000000..38cc27a
--- /dev/null
+++ b/rails/homeworks/capybara/config.ru
@@ -0,0 +1,6 @@
+# This file is used by Rack-based servers to start the application.
+
+require_relative "config/environment"
+
+run Rails.application
+Rails.application.load_server
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/application.rb b/rails/homeworks/capybara/config/application.rb
new file mode 100644
index 0000000..cfb18fc
--- /dev/null
+++ b/rails/homeworks/capybara/config/application.rb
@@ -0,0 +1,41 @@
+require_relative "boot"
+
+require "rails"
+# Pick the frameworks you want:
+require "active_model/railtie"
+# require "active_job/railtie"
+require "active_record/railtie"
+# require "active_storage/engine"
+require "action_controller/railtie"
+require "action_mailer/railtie"
+# require "action_mailbox/engine"
+# require "action_text/engine"
+require "action_view/railtie"
+# require "action_cable/engine"
+# require "rails/test_unit/railtie"
+
+# Require the gems listed in Gemfile, including any gems
+# you've limited to :test, :development, or :production.
+Bundler.require(*Rails.groups)
+
+module Capybara
+  class Application < Rails::Application
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults 7.0
+
+    config.action_mailer.default_url_options = { host: 'localhost:3000' }
+    config.action_mailer.delivery_method = :smtp
+    config.action_mailer.smtp_settings = { address: '0.0.0.0', port: 1025 }
+    config.action_mailer.raise_delivery_errors = false
+    # Configuration for the application, engines, and railties goes here.
+    #
+    # These settings can be overridden in specific environments using the files
+    # in config/environments, which are processed later.
+    #
+    # config.time_zone = "Central Time (US & Canada)"
+    # config.eager_load_paths << Rails.root.join("extras")
+
+    # Don't generate system test files.
+    config.generators.system_tests = nil
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/boot.rb b/rails/homeworks/capybara/config/boot.rb
new file mode 100644
index 0000000..2820116
--- /dev/null
+++ b/rails/homeworks/capybara/config/boot.rb
@@ -0,0 +1,3 @@
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+
+require "bundler/setup" # Set up gems listed in the Gemfile.
diff --git a/rails/homeworks/capybara/config/credentials.yml.enc b/rails/homeworks/capybara/config/credentials.yml.enc
new file mode 100644
index 0000000..f3a1565
--- /dev/null
+++ b/rails/homeworks/capybara/config/credentials.yml.enc
@@ -0,0 +1 @@
+Ro91FewqPvZU0Ybj7yWz2apVRRGiXhTpdz5AMxM27amdmloVxAVDfYmdmBAnas9rEh4mbVIbY3pBuuPCyZwVozHcNoGSTXRxREIGCzqxUIS4Jg+8Y0aZMbWlvzr6trz3wcqjtyaeefynv4CQpGbD71enMoi8qvV/vqfW+H+wuwGtIkh5qle9xw3SIxG5YxL6BgOo40jWadKfCOUGv+laIsluXuoAejHeBc18HbczLLjCbZGaS3ki6nN8gCyIrwMo9YwwnTr4OX3UWDVbzdC6oPWUvwNR1gmrmxulwJUDXvejh64le3vH+gSEV/uCdNJJPW65p5SrKj4o19eOSt0r73Mbb0QFlWoRFUWl1SuqXtv9OG56SVaxzgSJiZisQF6MN/rhPh7PTcS1oXFny0nG0dNBY7CY5VIY0r1g--pI8ayETrsjeWuqgN--cuuT/uE7t0+rzfCMnjdT0Q==
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/database.yml b/rails/homeworks/capybara/config/database.yml
new file mode 100644
index 0000000..8ebe06f
--- /dev/null
+++ b/rails/homeworks/capybara/config/database.yml
@@ -0,0 +1,86 @@
+# PostgreSQL. Versions 9.3 and up are supported.
+#
+# Install the pg driver:
+#   gem install pg
+# On macOS with Homebrew:
+#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
+# On macOS with MacPorts:
+#   gem install pg -- --with-pg-config=/opt/local/lib/postgresql84/bin/pg_config
+# On Windows:
+#   gem install pg
+#       Choose the win32 build.
+#       Install PostgreSQL and put its /bin directory on your path.
+#
+# Configure Using Gemfile
+# gem "pg"
+#
+default: &default
+  adapter: postgresql
+  encoding: unicode
+  # For details on connection pooling, see Rails configuration guide
+  # https://guides.rubyonrails.org/configuring.html#database-pooling
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+
+development:
+  <<: *default
+  database: capybara_development
+
+  # The specified database role being used to connect to postgres.
+  # To create additional roles in postgres see `$ createuser --help`.
+  # When left blank, postgres will use the default role. This is
+  # the same name as the operating system user running Rails.
+  #username: capybara
+
+  # The password associated with the postgres role (username).
+  #password:
+
+  # Connect on a TCP socket. Omitted by default since the client uses a
+  # domain socket that doesn't need configuration. Windows does not have
+  # domain sockets, so uncomment these lines.
+  #host: localhost
+
+  # The TCP port the server listens on. Defaults to 5432.
+  # If your server runs on a different port number, change accordingly.
+  #port: 5432
+
+  # Schema search path. The server defaults to $user,public
+  #schema_search_path: myapp,sharedapp,public
+
+  # Minimum log levels, in increasing order:
+  #   debug5, debug4, debug3, debug2, debug1,
+  #   log, notice, warning, error, fatal, and panic
+  # Defaults to warning.
+  #min_messages: notice
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: capybara_test
+
+# As with config/credentials.yml, you never want to store sensitive information,
+# like your database password, in your source code. If your source code is
+# ever seen by anyone, they now have access to your database.
+#
+# Instead, provide the password or a full connection URL as an environment
+# variable when you boot the app. For example:
+#
+#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
+#
+# If the connection URL is provided in the special DATABASE_URL environment
+# variable, Rails will automatically merge its configuration values on top of
+# the values provided in this file. Alternatively, you can specify a connection
+# URL environment variable explicitly:
+#
+#   production:
+#     url: <%= ENV["MY_APP_DATABASE_URL"] %>
+#
+# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
+# for a full overview on how database connection configuration can be specified.
+#
+production:
+  <<: *default
+  database: capybara_production
+  username: capybara
+  password: <%= ENV["CAPYBARA_DATABASE_PASSWORD"] %>
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/environment.rb b/rails/homeworks/capybara/config/environment.rb
new file mode 100644
index 0000000..445c788
--- /dev/null
+++ b/rails/homeworks/capybara/config/environment.rb
@@ -0,0 +1,5 @@
+# Load the Rails application.
+require_relative "application"
+
+# Initialize the Rails application.
+Rails.application.initialize!
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/environments/development.rb b/rails/homeworks/capybara/config/environments/development.rb
new file mode 100644
index 0000000..851adc5
--- /dev/null
+++ b/rails/homeworks/capybara/config/environments/development.rb
@@ -0,0 +1,62 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # In the development environment your application's code is reloaded any time
+  # it changes. This slows down response time but is perfect for development
+  # since you don't have to restart the web server when you make code changes.
+  config.cache_classes = false
+
+  # Do not eager load code on boot.
+  config.eager_load = false
+
+  # Show full error reports.
+  config.consider_all_requests_local = true
+
+  # Enable server timing
+  config.server_timing = true
+
+  # Enable/disable caching. By default caching is disabled.
+  # Run rails dev:cache to toggle caching.
+  if Rails.root.join("tmp/caching-dev.txt").exist?
+    config.action_controller.perform_caching = true
+    config.action_controller.enable_fragment_cache_logging = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      "Cache-Control" => "public, max-age=#{2.days.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
+
+  # Print deprecation notices to the Rails logger.
+  config.active_support.deprecation = :log
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raise an error on page load if there are pending migrations.
+  config.active_record.migration_error = :page_load
+
+  # Highlight code that triggered database queries in logs.
+  config.active_record.verbose_query_logs = true
+
+  # Suppress logger output for asset requests.
+  config.assets.quiet = true
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+
+  # Uncomment if you wish to allow Action Cable access from any origin.
+  # config.action_cable.disable_request_forgery_protection = true
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/environments/production.rb b/rails/homeworks/capybara/config/environments/production.rb
new file mode 100644
index 0000000..6aee001
--- /dev/null
+++ b/rails/homeworks/capybara/config/environments/production.rb
@@ -0,0 +1,75 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Code is not reloaded between requests.
+  config.cache_classes = true
+
+  # Eager load code on boot. This eager loads most of Rails and
+  # your application in memory, allowing both threaded web servers
+  # and those relying on copy on write to perform better.
+  # Rake tasks automatically ignore this option for performance.
+  config.eager_load = true
+
+  # Full error reports are disabled and caching is turned on.
+  config.consider_all_requests_local       = false
+  config.action_controller.perform_caching = true
+
+  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  # config.require_master_key = true
+
+  # Disable serving static files from the `/public` folder by default since
+  # Apache or NGINX already handles this.
+  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
+
+  # Compress CSS using a preprocessor.
+  # config.assets.css_compressor = :sass
+
+  # Do not fallback to assets pipeline if a precompiled asset is missed.
+  config.assets.compile = false
+
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.asset_host = "http://assets.example.com"
+
+  # Specifies the header that your server uses for sending files.
+  # config.action_dispatch.x_sendfile_header = "X-Sendfile" # for Apache
+  # config.action_dispatch.x_sendfile_header = "X-Accel-Redirect" # for NGINX
+
+  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
+  # config.force_ssl = true
+
+  # Include generic and useful information about system operation, but avoid logging too much
+  # information to avoid inadvertent exposure of personally identifiable information (PII).
+  config.log_level = :info
+
+  # Prepend all log lines with the following tags.
+  config.log_tags = [ :request_id ]
+
+  # Use a different cache store in production.
+  # config.cache_store = :mem_cache_store
+
+  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
+  # the I18n.default_locale when a translation cannot be found).
+  config.i18n.fallbacks = true
+
+  # Don't log any deprecations.
+  config.active_support.report_deprecations = false
+
+  # Use default logging formatter so that PID and timestamp are not suppressed.
+  config.log_formatter = ::Logger::Formatter.new
+
+  # Use a different logger for distributed setups.
+  # require "syslog/logger"
+  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
+
+  if ENV["RAILS_LOG_TO_STDOUT"].present?
+    logger           = ActiveSupport::Logger.new(STDOUT)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/environments/test.rb b/rails/homeworks/capybara/config/environments/test.rb
new file mode 100644
index 0000000..da62dfc
--- /dev/null
+++ b/rails/homeworks/capybara/config/environments/test.rb
@@ -0,0 +1,50 @@
+require "active_support/core_ext/integer/time"
+
+# The test environment is used exclusively to run your application's
+# test suite. You never need to work with it otherwise. Remember that
+# your test database is "scratch space" for the test suite and is wiped
+# and recreated between test runs. Don't rely on the data there!
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Turn false under Spring and add config.action_view.cache_template_loading = true.
+  config.cache_classes = true
+
+  # Eager loading loads your whole application. When running a single test locally,
+  # this probably isn't necessary. It's a good idea to do in a continuous integration
+  # system, or in some way before deploying your code.
+  config.eager_load = ENV["CI"].present?
+
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = {
+    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
+  }
+
+  # Show full error reports and disable caching.
+  config.consider_all_requests_local       = true
+  config.action_controller.perform_caching = false
+  config.cache_store = :null_store
+
+  # Raise exceptions instead of rendering exception templates.
+  config.action_dispatch.show_exceptions = false
+
+  # Disable request forgery protection in test environment.
+  config.action_controller.allow_forgery_protection = false
+
+  # Print deprecation notices to the stderr.
+  config.active_support.deprecation = :stderr
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/initializers/assets.rb b/rails/homeworks/capybara/config/initializers/assets.rb
new file mode 100644
index 0000000..bd8332f
--- /dev/null
+++ b/rails/homeworks/capybara/config/initializers/assets.rb
@@ -0,0 +1,12 @@
+# Be sure to restart your server when you modify this file.
+
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = "1.0"
+
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/initializers/content_security_policy.rb b/rails/homeworks/capybara/config/initializers/content_security_policy.rb
new file mode 100644
index 0000000..b713b2f
--- /dev/null
+++ b/rails/homeworks/capybara/config/initializers/content_security_policy.rb
@@ -0,0 +1,25 @@
+# Be sure to restart your server when you modify this file.
+
+# Define an application-wide content security policy.
+# See the Securing Rails Applications Guide for more information:
+# https://guides.rubyonrails.org/security.html#content-security-policy-header
+
+# Rails.application.configure do
+#   config.content_security_policy do |policy|
+#     policy.default_src :self, :https
+#     policy.font_src    :self, :https, :data
+#     policy.img_src     :self, :https, :data
+#     policy.object_src  :none
+#     policy.script_src  :self, :https
+#     policy.style_src   :self, :https
+#     # Specify URI for violation reports
+#     # policy.report_uri "/csp-violation-report-endpoint"
+#   end
+#
+#   # Generate session nonces for permitted importmap and inline scripts
+#   config.content_security_policy_nonce_generator = ->(request) { request.session.id.to_s }
+#   config.content_security_policy_nonce_directives = %w(script-src)
+#
+#   # Report violations without enforcing the policy.
+#   # config.content_security_policy_report_only = true
+# end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/initializers/filter_parameter_logging.rb b/rails/homeworks/capybara/config/initializers/filter_parameter_logging.rb
new file mode 100644
index 0000000..b4db5f6
--- /dev/null
+++ b/rails/homeworks/capybara/config/initializers/filter_parameter_logging.rb
@@ -0,0 +1,8 @@
+# Be sure to restart your server when you modify this file.
+
+# Configure parameters to be filtered from the log file. Use this to limit dissemination of
+# sensitive information. See the ActiveSupport::ParameterFilter documentation for supported
+# notations and behaviors.
+Rails.application.config.filter_parameters += [
+  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
+]
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/initializers/inflections.rb b/rails/homeworks/capybara/config/initializers/inflections.rb
new file mode 100644
index 0000000..df431d7
--- /dev/null
+++ b/rails/homeworks/capybara/config/initializers/inflections.rb
@@ -0,0 +1,16 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new inflection rules using the following format. Inflections
+# are locale specific, and you may define rules for as many different
+# locales as you wish. All of these examples are active by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.plural /^(ox)$/i, "\\1en"
+#   inflect.singular /^(ox)en/i, "\\1"
+#   inflect.irregular "person", "people"
+#   inflect.uncountable %w( fish sheep )
+# end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym "RESTful"
+# end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/initializers/permissions_policy.rb b/rails/homeworks/capybara/config/initializers/permissions_policy.rb
new file mode 100644
index 0000000..dd30019
--- /dev/null
+++ b/rails/homeworks/capybara/config/initializers/permissions_policy.rb
@@ -0,0 +1,11 @@
+# Define an application-wide HTTP permissions policy. For further
+# information see https://developers.google.com/web/updates/2018/06/feature-policy
+#
+# Rails.application.config.permissions_policy do |f|
+#   f.camera      :none
+#   f.gyroscope   :none
+#   f.microphone  :none
+#   f.usb         :none
+#   f.fullscreen  :self
+#   f.payment     :self, "https://secure.example.com"
+# end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/locales/en.yml b/rails/homeworks/capybara/config/locales/en.yml
new file mode 100644
index 0000000..30c9973
--- /dev/null
+++ b/rails/homeworks/capybara/config/locales/en.yml
@@ -0,0 +1,33 @@
+# Files in the config/locales directory are used for internationalization
+# and are automatically loaded by Rails. If you want to use locales other
+# than English, add the necessary files in this directory.
+#
+# To use the locales, use `I18n.t`:
+#
+#     I18n.t "hello"
+#
+# In views, this is aliased to just `t`:
+#
+#     <%= t("hello") %>
+#
+# To use a different locale, set it with `I18n.locale`:
+#
+#     I18n.locale = :es
+#
+# This would use the information in config/locales/es.yml.
+#
+# The following keys must be escaped otherwise they will not be retrieved by
+# the default I18n backend:
+#
+# true, false, on, off, yes, no
+#
+# Instead, surround them with single quotes.
+#
+# en:
+#   "true": "foo"
+#
+# To learn more, please read the Rails Internationalization guide
+# available at https://guides.rubyonrails.org/i18n.html.
+
+en:
+  hello: "Hello world"
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/puma.rb b/rails/homeworks/capybara/config/puma.rb
new file mode 100644
index 0000000..411b18d
--- /dev/null
+++ b/rails/homeworks/capybara/config/puma.rb
@@ -0,0 +1,43 @@
+# Puma can serve each request in a thread from an internal thread pool.
+# The `threads` method setting takes two numbers: a minimum and maximum.
+# Any libraries that use thread pools should be configured to match
+# the maximum value specified for Puma. Default is set to 5 threads for minimum
+# and maximum; this matches the default thread size of Active Record.
+#
+max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
+min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count }
+threads min_threads_count, max_threads_count
+
+# Specifies the `worker_timeout` threshold that Puma will use to wait before
+# terminating a worker in development environments.
+#
+worker_timeout 3600 if ENV.fetch("RAILS_ENV", "development") == "development"
+
+# Specifies the `port` that Puma will listen on to receive requests; default is 3000.
+#
+port ENV.fetch("PORT") { 3000 }
+
+# Specifies the `environment` that Puma will run in.
+#
+environment ENV.fetch("RAILS_ENV") { "development" }
+
+# Specifies the `pidfile` that Puma will use.
+pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
+
+# Specifies the number of `workers` to boot in clustered mode.
+# Workers are forked web server processes. If using threads and workers together
+# the concurrency of the application would be max `threads` * `workers`.
+# Workers do not work on JRuby or Windows (both of which do not support
+# processes).
+#
+# workers ENV.fetch("WEB_CONCURRENCY") { 2 }
+
+# Use the `preload_app!` method when specifying a `workers` number.
+# This directive tells Puma to first boot the application and load code
+# before forking the application. This takes advantage of Copy On Write
+# process behavior so workers use less memory.
+#
+# preload_app!
+
+# Allow puma to be restarted by `bin/rails restart` command.
+plugin :tmp_restart
\ No newline at end of file
diff --git a/rails/homeworks/capybara/config/routes.rb b/rails/homeworks/capybara/config/routes.rb
new file mode 100644
index 0000000..8d8ad73
--- /dev/null
+++ b/rails/homeworks/capybara/config/routes.rb
@@ -0,0 +1,25 @@
+Rails.application.routes.draw do
+  # Define your application routes per the DSL in https://guides.rubyonrails.org/routing.html
+
+  # Defines the root path route ("/")
+  root "bands#index"
+
+  resource :session, only: [:new, :create, :destroy]
+
+  resources :users, only: [:index, :show, :new, :create] do
+    get :activate, on: :collection
+    post :toggle_admin, on: :member
+  end
+
+  resources :bands do
+    resources :albums, only: [:new]
+  end
+
+  resources :albums, only: [:show, :create, :edit, :update, :destroy] do
+    resources :tracks, only: [:new]
+  end
+
+  resources :tracks, only: [:show, :create, :edit, :update, :destroy]
+
+  resources :notes, only: [:create, :destroy]
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/db/migrate/20220621163908_create_users.rb b/rails/homeworks/capybara/db/migrate/20220621163908_create_users.rb
new file mode 100644
index 0000000..10fa186
--- /dev/null
+++ b/rails/homeworks/capybara/db/migrate/20220621163908_create_users.rb
@@ -0,0 +1,13 @@
+class CreateUsers < ActiveRecord::Migration[7.0]
+  def change
+    create_table :users do |t|
+      t.string :email, null: false
+      t.string :password_digest, null: false
+      t.string :session_token, null: false
+
+      t.timestamps
+    end
+    add_index :users, :email, unique: true
+    add_index :users, :session_token, unique: true
+  end
+end
diff --git a/rails/homeworks/capybara/db/migrate/20220621190221_create_bands.rb b/rails/homeworks/capybara/db/migrate/20220621190221_create_bands.rb
new file mode 100644
index 0000000..363ef76
--- /dev/null
+++ b/rails/homeworks/capybara/db/migrate/20220621190221_create_bands.rb
@@ -0,0 +1,10 @@
+class CreateBands < ActiveRecord::Migration[7.0]
+  def change
+    create_table :bands do |t|
+      t.string :name, null: false
+
+      t.timestamps
+    end
+    add_index :bands, :name, unique: true
+  end
+end
diff --git a/rails/homeworks/capybara/db/migrate/20220621192955_create_albums.rb b/rails/homeworks/capybara/db/migrate/20220621192955_create_albums.rb
new file mode 100644
index 0000000..e2b7f40
--- /dev/null
+++ b/rails/homeworks/capybara/db/migrate/20220621192955_create_albums.rb
@@ -0,0 +1,13 @@
+class CreateAlbums < ActiveRecord::Migration[7.0]
+  def change
+    create_table :albums do |t|
+      t.string :title, null: false
+      t.references :band, null: false, foreign_key: true, index: false
+      t.integer :year, null: false
+      t.boolean :live, null: false, default: false
+
+      t.timestamps
+    end
+    add_index :albums, %i(band_id title), unique: true
+  end
+end
diff --git a/rails/homeworks/capybara/db/migrate/20220621194319_create_tracks.rb b/rails/homeworks/capybara/db/migrate/20220621194319_create_tracks.rb
new file mode 100644
index 0000000..e77642c
--- /dev/null
+++ b/rails/homeworks/capybara/db/migrate/20220621194319_create_tracks.rb
@@ -0,0 +1,14 @@
+class CreateTracks < ActiveRecord::Migration[7.0]
+  def change
+    create_table :tracks do |t|
+      t.string :title, null: false
+      t.references :album, null: false, foreign_key: true, index: false
+      t.integer :ord, null: false
+      t.boolean :bonus, null: false, default: false
+      t.text :lyrics
+
+      t.timestamps
+    end
+    add_index :tracks, %i(album_id ord), unique: true
+  end
+end
diff --git a/rails/homeworks/capybara/db/migrate/20220621212523_create_notes.rb b/rails/homeworks/capybara/db/migrate/20220621212523_create_notes.rb
new file mode 100644
index 0000000..083abf4
--- /dev/null
+++ b/rails/homeworks/capybara/db/migrate/20220621212523_create_notes.rb
@@ -0,0 +1,11 @@
+class CreateNotes < ActiveRecord::Migration[7.0]
+  def change
+    create_table :notes do |t|
+      t.references :track, null: false, foreign_key: true
+      t.references :author, null: false, foreign_key: { to_table: :users }
+      t.text :content, null: false
+
+      t.timestamps
+    end
+  end
+end
diff --git a/rails/homeworks/capybara/db/migrate/20220621221109_add_activation_columns_to_users.rb b/rails/homeworks/capybara/db/migrate/20220621221109_add_activation_columns_to_users.rb
new file mode 100644
index 0000000..898d151
--- /dev/null
+++ b/rails/homeworks/capybara/db/migrate/20220621221109_add_activation_columns_to_users.rb
@@ -0,0 +1,7 @@
+class AddActivationColumnsToUsers < ActiveRecord::Migration[7.0]
+  def change
+    add_column :users, :activated, :boolean, null: false, default: false
+    add_column :users, :activation_token, :string, null: false
+    add_index :users, :activation_token, unique: true
+  end
+end
diff --git a/rails/homeworks/capybara/db/migrate/20220622161834_add_admin_to_users.rb b/rails/homeworks/capybara/db/migrate/20220622161834_add_admin_to_users.rb
new file mode 100644
index 0000000..61a06a4
--- /dev/null
+++ b/rails/homeworks/capybara/db/migrate/20220622161834_add_admin_to_users.rb
@@ -0,0 +1,5 @@
+class AddAdminToUsers < ActiveRecord::Migration[7.0]
+  def change
+    add_column :users, :admin, :boolean, null: false, default: false
+  end
+end
diff --git a/rails/homeworks/capybara/db/schema.rb b/rails/homeworks/capybara/db/schema.rb
new file mode 100644
index 0000000..7953dc8
--- /dev/null
+++ b/rails/homeworks/capybara/db/schema.rb
@@ -0,0 +1,73 @@
+# This file is auto-generated from the current state of the database. Instead
+# of editing this file, please use the migrations feature of Active Record to
+# incrementally modify your database, and then regenerate this schema definition.
+#
+# This file is the source Rails uses to define your schema when running `bin/rails
+# db:schema:load`. When creating a new database, `bin/rails db:schema:load` tends to
+# be faster and is potentially less error prone than running all of your
+# migrations from scratch. Old migrations may fail to apply correctly if those
+# migrations use external dependencies or application code.
+#
+# It's strongly recommended that you check this file into your version control system.
+
+ActiveRecord::Schema[7.0].define(version: 2022_06_22_161834) do
+  # These are extensions that must be enabled in order to support this database
+  enable_extension "plpgsql"
+
+  create_table "albums", force: :cascade do |t|
+    t.string "title", null: false
+    t.bigint "band_id", null: false
+    t.integer "year", null: false
+    t.boolean "live", default: false, null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["band_id", "title"], name: "index_albums_on_band_id_and_title", unique: true
+  end
+
+  create_table "bands", force: :cascade do |t|
+    t.string "name", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["name"], name: "index_bands_on_name", unique: true
+  end
+
+  create_table "notes", force: :cascade do |t|
+    t.bigint "track_id", null: false
+    t.bigint "author_id", null: false
+    t.text "content", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["author_id"], name: "index_notes_on_author_id"
+    t.index ["track_id"], name: "index_notes_on_track_id"
+  end
+
+  create_table "tracks", force: :cascade do |t|
+    t.string "title", null: false
+    t.bigint "album_id", null: false
+    t.integer "ord", null: false
+    t.boolean "bonus", default: false, null: false
+    t.text "lyrics"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["album_id", "ord"], name: "index_tracks_on_album_id_and_ord", unique: true
+  end
+
+  create_table "users", force: :cascade do |t|
+    t.string "email", null: false
+    t.string "password_digest", null: false
+    t.string "session_token", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.boolean "activated", default: false, null: false
+    t.string "activation_token", null: false
+    t.boolean "admin", default: false, null: false
+    t.index ["activation_token"], name: "index_users_on_activation_token", unique: true
+    t.index ["email"], name: "index_users_on_email", unique: true
+    t.index ["session_token"], name: "index_users_on_session_token", unique: true
+  end
+
+  add_foreign_key "albums", "bands"
+  add_foreign_key "notes", "tracks"
+  add_foreign_key "notes", "users", column: "author_id"
+  add_foreign_key "tracks", "albums"
+end
\ No newline at end of file
diff --git a/rails/homeworks/capybara/db/seeds.rb b/rails/homeworks/capybara/db/seeds.rb
new file mode 100644
index 0000000..555c37c
--- /dev/null
+++ b/rails/homeworks/capybara/db/seeds.rb
@@ -0,0 +1,7 @@
+# This file should contain all the record creation needed to seed the database with its default values.
+# The data can then be loaded with the bin/rails db:seed command (or created alongside the database with db:setup).
+#
+# Examples:
+#
+#   movies = Movie.create([{ name: "Star Wars" }, { name: "Lord of the Rings" }])
+#   Character.create(name: "Luke", movie: movies.first)
\ No newline at end of file
diff --git a/rails/homeworks/capybara/lib/assets/.keep b/rails/homeworks/capybara/lib/assets/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/lib/tasks/.keep b/rails/homeworks/capybara/lib/tasks/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/log/.keep b/rails/homeworks/capybara/log/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/public/404.html b/rails/homeworks/capybara/public/404.html
new file mode 100644
index 0000000..cb93ac7
--- /dev/null
+++ b/rails/homeworks/capybara/public/404.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The page you were looking for doesn't exist (404)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/404.html -->
+  <div class="dialog">
+    <div>
+      <h1>The page you were looking for doesn't exist.</h1>
+      <p>You may have mistyped the address or the page may have moved.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/capybara/public/422.html b/rails/homeworks/capybara/public/422.html
new file mode 100644
index 0000000..aa1a374
--- /dev/null
+++ b/rails/homeworks/capybara/public/422.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The change you wanted was rejected (422)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/422.html -->
+  <div class="dialog">
+    <div>
+      <h1>The change you wanted was rejected.</h1>
+      <p>Maybe you tried to change something you didn't have access to.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/capybara/public/500.html b/rails/homeworks/capybara/public/500.html
new file mode 100644
index 0000000..0fd6fca
--- /dev/null
+++ b/rails/homeworks/capybara/public/500.html
@@ -0,0 +1,66 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>We're sorry, but something went wrong (500)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/500.html -->
+  <div class="dialog">
+    <div>
+      <h1>We're sorry, but something went wrong.</h1>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/capybara/public/apple-touch-icon-precomposed.png b/rails/homeworks/capybara/public/apple-touch-icon-precomposed.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/public/apple-touch-icon.png b/rails/homeworks/capybara/public/apple-touch-icon.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/public/favicon.ico b/rails/homeworks/capybara/public/favicon.ico
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/public/robots.txt b/rails/homeworks/capybara/public/robots.txt
new file mode 100644
index 0000000..0285b2d
--- /dev/null
+++ b/rails/homeworks/capybara/public/robots.txt
@@ -0,0 +1 @@
+# See https://www.robotstxt.org/robotstxt.html for documentation on how to use the robots.txt file
\ No newline at end of file
diff --git a/rails/homeworks/capybara/tmp/.keep b/rails/homeworks/capybara/tmp/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/tmp/pids/.keep b/rails/homeworks/capybara/tmp/pids/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/capybara/vendor/.keep b/rails/homeworks/capybara/vendor/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/.gitattributes b/rails/homeworks/helpers-layouts-mailer/.gitattributes
new file mode 100644
index 0000000..34fb547
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/.gitattributes
@@ -0,0 +1,7 @@
+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/.gitignore b/rails/homeworks/helpers-layouts-mailer/.gitignore
new file mode 100644
index 0000000..4f0da6f
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/.gitignore
@@ -0,0 +1,26 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/.ruby-version b/rails/homeworks/helpers-layouts-mailer/.ruby-version
new file mode 100644
index 0000000..94ff29c
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/.ruby-version
@@ -0,0 +1 @@
+3.1.1
diff --git a/rails/homeworks/helpers-layouts-mailer/Gemfile b/rails/homeworks/helpers-layouts-mailer/Gemfile
new file mode 100644
index 0000000..1cd5cea
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/Gemfile
@@ -0,0 +1,36 @@
+source "https://rubygems.org"
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+ruby "3.1.1"
+
+# Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
+gem "rails", "~> 7.0.2", ">= 7.0.2.2"
+
+# The original asset pipeline for Rails [https://github.com/rails/sprockets-rails]
+gem "sprockets-rails"
+
+# Use postgresql as the database for Active Record
+gem "pg", "~> 1.1"
+
+# Use the Puma web server [https://github.com/puma/puma]
+gem "puma", "~> 5.0"
+
+# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
+gem "tzinfo-data", platforms: %i[ mingw mswin x64_mingw jruby ]
+
+gem "bcrypt"
+
+group :development, :test do
+  # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
+  # gem "debug", platforms: %i[ mri mingw x64_mingw ]
+  gem "byebug", platforms: %i[ mri mingw x64_mingw ]
+end
+
+group :development do
+  # Speed up commands on slow machines / big apps [https://github.com/rails/spring]
+  # gem "spring"
+  gem "annotate"
+  gem "pry-rails"
+  gem "better_errors"
+  gem "binding_of_caller"
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/Gemfile.lock b/rails/homeworks/helpers-layouts-mailer/Gemfile.lock
new file mode 100644
index 0000000..24c1be0
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/Gemfile.lock
@@ -0,0 +1,198 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailbox (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (>= 2.7.1)
+      net-imap
+      net-pop
+      net-smtp
+    actionmailer (7.0.3)
+      actionpack (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (~> 2.5, >= 2.5.4)
+      net-imap
+      net-pop
+      net-smtp
+      rails-dom-testing (~> 2.0)
+    actionpack (7.0.3)
+      actionview (= 7.0.3)
+      activesupport (= 7.0.3)
+      rack (~> 2.0, >= 2.2.0)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (7.0.3)
+      actionpack (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.6.0)
+      nokogiri (>= 1.8.5)
+    actionview (7.0.3)
+      activesupport (= 7.0.3)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.3.6)
+    activemodel (7.0.3)
+      activesupport (= 7.0.3)
+    activerecord (7.0.3)
+      activemodel (= 7.0.3)
+      activesupport (= 7.0.3)
+    activestorage (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activesupport (= 7.0.3)
+      marcel (~> 1.0)
+      mini_mime (>= 1.1.0)
+    activesupport (7.0.3)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+    addressable (2.8.0)
+      public_suffix (>= 2.0.2, < 5.0)
+    annotate (3.2.0)
+      activerecord (>= 3.2, < 8.0)
+      rake (>= 10.4, < 14.0)
+    bcrypt (3.1.18)
+    better_errors (2.9.1)
+      coderay (>= 1.0.0)
+      erubi (>= 1.0.0)
+      rack (>= 0.9.0)
+    binding_of_caller (1.0.0)
+      debug_inspector (>= 0.0.1)
+    builder (3.2.4)
+    byebug (11.1.3)
+    coderay (1.1.3)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    debug_inspector (1.1.0)
+    digest (3.1.0)
+    erubi (1.10.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
+      concurrent-ruby (~> 1.0)
+    launchy (2.5.0)
+      addressable (~> 2.7)
+    loofah (2.18.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (1.0.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    minitest (5.16.2)
+    net-imap (0.2.3)
+      digest
+      net-protocol
+      strscan
+    net-pop (0.1.1)
+      digest
+      net-protocol
+      timeout
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    pg (1.4.1)
+    pry (0.14.1)
+      coderay (~> 1.1)
+      method_source (~> 1.0)
+    pry-rails (0.3.9)
+      pry (>= 0.10.4)
+    public_suffix (4.0.7)
+    puma (5.6.4)
+      nio4r (~> 2.0)
+    racc (1.6.0)
+    rack (2.2.4)
+    rack-test (2.0.2)
+      rack (>= 1.3)
+    rails (7.0.3)
+      actioncable (= 7.0.3)
+      actionmailbox (= 7.0.3)
+      actionmailer (= 7.0.3)
+      actionpack (= 7.0.3)
+      actiontext (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activemodel (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      bundler (>= 1.15.0)
+      railties (= 7.0.3)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.4.3)
+      loofah (~> 2.3)
+    railties (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      method_source
+      rake (>= 12.2)
+      thor (~> 1.0)
+      zeitwerk (~> 2.5)
+    rake (13.0.6)
+    sprockets (4.1.1)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.4.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      sprockets (>= 3.0.0)
+    strscan (3.0.3)
+    thor (1.2.1)
+    timeout (0.3.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    websocket-driver (0.7.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
+    zeitwerk (2.6.0)
+
+PLATFORMS
+  x86_64-darwin-20
+
+DEPENDENCIES
+  annotate
+  bcrypt
+  better_errors
+  binding_of_caller
+  byebug
+  pg (~> 1.1)
+  pry-rails
+  puma (~> 5.0)
+  rails (~> 7.0.2, >= 7.0.2.2)
+  sprockets-rails
+  tzinfo-data
+
+RUBY VERSION
+   ruby 3.1.1p18
+
+BUNDLED WITH
+   2.3.14
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/README.md b/rails/homeworks/helpers-layouts-mailer/README.md
new file mode 100644
index 0000000..cfb0907
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/README.md
@@ -0,0 +1,147 @@
+# Helpers, Layouts, And Mailers Homework
+
+For this homework assignment, you will be building on the solution for 99 Cats
+II: Auth. Find the solution in the repo accessed through the `Download Project`
+button at the bottom of this page. Clone the repo, `cd` inside your local copy,
+then run `bundle install` and `bundle exec rails db:setup` to set it up.
+
+## Topic 1: View Helpers
+
+Isn't it pesky to have to rewrite the code for the `form_authenticity_token`
+field over and over? Let's abstract it into a simple helper method that you can
+use across your views.
+
+Open __app/helpers/application_helper.rb__ and write a new method called
+`auth_token`. As a refresher, your auth token code in your views should look
+something like this:
+
+```html
+<input
+  type="hidden"
+  name="authenticity_token"
+  value="<%= form_authenticity_token %>"
+/>
+```
+
+Put this code in your new `auth_token` method, but with a few changes. First,
+you need to wrap the input tag in a string and call `#html_safe` on it.
+Otherwise, your `auth_token` method will output the string literal for your
+input tag. Secondly, now that your input tag is little more than a string in
+Ruby-land, you shouldn't interpolate the actual `form_authenticity_token` using
+erb tags. Instead, just interpolate `form_authenticity_token` using the string
+interpolation syntax you know and love (`#{}`).
+
+Sweet! Looking good? Now go through your app and replace all of the
+`form_authenticity_token` input fields with calls to your snazzy new method,
+`<%= auth_token %>`, to dry up your code and simplify your life.
+
+## Topic 2: Layouts
+
+You've been using layouts in Rails every day without even knowing it! Check
+out your __application.html.erb__ file. In particular, notice the `<%= yield %>`
+tag in the middle of the layout. This will yield in the content for whatever
+page you're on, whether that's the cats index or the new user form.
+
+Now, suppose you wanted to add a footer on your __application.html.erb__ layout.
+You want your footer to display a paragraph describing your site on every page
+of your site. In addition, you want it to display a line describing the
+particular page the user is on. This is a perfect time to use Rails's
+`content_for` method.
+
+First, create a footer section in your __application.html.erb__ at the end of
+the `body` tag and write a short blurb describing your site. Verify that this
+shows up on every page as you navigate around in `localhost`.
+
+Next, add a second `yield` tag to insert the custom footer content within
+the new footer section. It should look something like this:
+
+```erb
+<footer>
+  This is our 99 Cats site. Please feel free to browse!
+
+  <%= yield :footer %>
+</footer>
+```
+
+Now, time to add some page specific content. Go through each of your views, and
+add a line specific to that page. It should look something like this:
+
+```erb
+<p>Other content for the cats index goes here</p>
+
+<% content_for :footer do %>
+  <p>This is the cats index page.</p>
+<% end %>
+```
+
+Finished? Navigate around your site in localhost. Make sure that the main body
+of each page appears in the main `yield` section of the layout and that your
+footer-specific content appears in the footer.
+
+## Topic 3: Action Mailer
+
+1. Activate Action Mailer by uncommenting `require "action_mailer/railtie"` in
+   __config/application.rb__.
+
+2. Create a user mailer to welcome new users to your account. The `rails g
+   mailer User` command will create a new mailer class file in
+   __app/mailers/user_mailer.rb__.
+
+   ```ruby
+   # app/mailers/user_mailer.rb
+
+   class UserMailer < ApplicationMailer
+   end
+   ```
+
+3. Implement a `#welcome_email` method that will email a user from
+   `99catsadmin@appacademy.io`. (You don't actually have an email address stored
+   for the user; for now, just pretend that their username will be an email
+   address.)
+
+   Need a hint? Refer back to the Action Mailer reading.
+
+   ```ruby
+   # app/mailers/user_mailer.rb
+
+   class UserMailer < ApplicationMailer
+     def welcome_email(user)
+       # your code here
+     end
+   end
+   ```
+
+4. Next, write the content for the email welcoming the user to the site. Create
+   a __welcome_email.html.erb__ file in __app/views/user_mailer/__ and fill it
+   in. Inform the user of their successfully created username and provide them
+   with a link to the sign-in page.
+
+   In addition to the __.html.erb__ file, make a text-only version in
+   __welcome_email.txt.erb__. Remember: omitting a text version of your email
+   could cause many filters interpret your email as spam!
+
+5. When a user signs up for your app, send them the welcome email. Where should
+   that code live within your existing `UsersController`? Implement the code.
+
+   Remember, you need a few things. You must call your new `welcome_email`
+   method, which returns a message, and call `deliver_now` on that message to
+   actually send it:
+
+   ```ruby
+   msg = UserMailer.welcome_email(@user)
+   msg.deliver_now
+   ```
+
+6. Test it out! Set up the `letter_opener` gem so that you can try out your code
+   on `localhost:3000`:
+
+   ```ruby
+   # Gemfile
+   gem 'letter_opener', group: :development
+
+   # config/environments/development.rb
+   config.action_mailer.delivery_method = :letter_opener
+   ```
+
+   The sent message should pop up in the browser if all went according to plan.
+   Congrats! You've Action Mailed!
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/Rakefile b/rails/homeworks/helpers-layouts-mailer/Rakefile
new file mode 100644
index 0000000..d298243
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/Rakefile
@@ -0,0 +1,6 @@
+# Add your own tasks in files placed in lib/tasks ending in .rake,
+# for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
+
+require_relative "config/application"
+
+Rails.application.load_tasks
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/assets/config/manifest.js b/rails/homeworks/helpers-layouts-mailer/app/assets/config/manifest.js
new file mode 100644
index 0000000..f83f92b
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/assets/config/manifest.js
@@ -0,0 +1,2 @@
+//= link_tree ../images
+//= link_directory ../stylesheets .css
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/assets/images/.keep b/rails/homeworks/helpers-layouts-mailer/app/assets/images/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/app/assets/stylesheets/application.css b/rails/homeworks/helpers-layouts-mailer/app/assets/stylesheets/application.css
new file mode 100644
index 0000000..e5faea8
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/assets/stylesheets/application.css
@@ -0,0 +1,168 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS and SCSS file within this directory, lib/assets/stylesheets, or any plugin's
+ * vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS/SCSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree .
+ *= require_self
+ */
+
+ html, body, section, article, h1, h2, p, nav, main, figure {
+   margin: 0;
+   border: 0;
+   padding: 0;
+   font: inherit;
+   text-align: inherit;
+   text-decoration: inherit;
+   color: inherit;
+   background: transparent;
+   font-family: 'Amatic SC', cursive;
+   font-size: 30px;
+ }
+
+nav {
+  width: 100%;
+  background-color: #000066;
+  height: 60px;
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  box-sizing: border-box;
+  padding: 0 20px;
+  color: yellow;
+}
+
+h1 {
+  font-size: 60px;
+  color: yellow;
+}
+
+a {
+  color: yellow;
+}
+
+
+nav a {
+  padding: 0px 10px;
+}
+
+table {
+  background-color: white;
+  margin: auto;
+}
+
+th {
+  background-color: #000066;
+  color: yellow;
+  padding: 10px 20px;
+}
+
+textarea, select, input {
+  font-family: 'Amatic SC', cursive;
+  background-color: inherit;
+  border: 0px;
+  border-bottom: 5px solid yellow;
+  font-size: 30px;
+  margin: 5px 10px;
+}
+
+input[type="submit"]:hover {
+  cursor: pointer;
+}
+
+input[type="submit"] {
+  font-weight: bold;
+}
+
+input:focus, select:focus, textarea:focus {
+  outline: none;
+}
+
+label {
+  font-weight: bold;
+  margin: 15px 0px;
+}
+
+textarea {
+  display: block;
+  margin: auto;
+  width: 300px;
+  background-color: white;
+}
+
+nav form {
+  display: inline;
+}
+
+nav input {
+  color: yellow;
+}
+
+.main-nav {
+  top: 0px;
+  z-index: 100;
+}
+
+.button_to div {
+  display: inline;
+}
+
+
+.jumbotron {
+  height: 500px;
+  width: 100%;
+  background-size: cover;
+  background-image: url("cat_jumbotron.jpg");
+}
+
+.jumbotron h1 {
+  font-size: 150px;
+  color: yellow;
+  position: absolute;
+  bottom: 120px;
+  right: 50px;
+}
+
+.cat-index-holder {
+  margin: 50px auto;
+  width: 920px;
+  background-color: #009999;
+}
+
+.cat-index {
+  width: 100%;
+  display: flex;
+  justify-content: space-around;
+  flex-wrap: wrap;
+}
+
+.cat-index-item {
+  padding: 20px;
+  margin: 20px 0;
+  width: 235px;
+  height: 280px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background-color: #000066;
+}
+
+.page {
+  display: flex;
+  justify-content: space-around;
+}
+
+.centered-box {
+  width: 500px;
+  margin: 50px 0;
+  background-color: #009999;
+  text-align: center;
+  padding: 50px;
+}
diff --git a/rails/homeworks/helpers-layouts-mailer/app/controllers/application_controller.rb b/rails/homeworks/helpers-layouts-mailer/app/controllers/application_controller.rb
new file mode 100644
index 0000000..c18276c
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/controllers/application_controller.rb
@@ -0,0 +1,33 @@
+class ApplicationController < ActionController::Base
+  # Expose `current_user` and `logged_in?` methods to the views
+  helper_method :current_user, :logged_in?
+
+  private
+
+  def current_user
+    return nil unless session[:session_token]
+    @current_user ||= User.find_by(session_token: session[:session_token])
+  end
+
+  def logged_in?
+    !!current_user
+  end
+
+  def login!(user)
+    @current_user = user
+    session[:session_token] = user.reset_session_token!
+  end
+
+  def logout!
+    current_user.try(:reset_session_token!)
+    session[:session_token] = nil
+  end
+
+  def require_logged_out
+    redirect_to cats_url if current_user
+  end
+
+  def require_logged_in
+    redirect_to new_session_url unless current_user
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/controllers/cat_rental_requests_controller.rb b/rails/homeworks/helpers-layouts-mailer/app/controllers/cat_rental_requests_controller.rb
new file mode 100644
index 0000000..b0448ec
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/controllers/cat_rental_requests_controller.rb
@@ -0,0 +1,51 @@
+class CatRentalRequestsController < ApplicationController
+  before_action :require_logged_in, only: %i(new create)
+  before_action :require_cat_ownership, only: %i(approve deny)
+  
+  def approve
+    current_cat_rental_request.approve!
+    redirect_to cat_url(current_cat)
+  end
+
+  def create
+    @rental_request = CatRentalRequest.new(cat_rental_request_params)
+    @rental_request.requester = current_user
+    if @rental_request.save
+      redirect_to cat_url(@rental_request.cat)
+    else
+      flash.now[:errors] = @rental_request.errors.full_messages
+      render :new
+    end
+  end
+
+  def deny
+    current_cat_rental_request.deny!
+    redirect_to cat_url(current_cat)
+  end
+
+  def new
+    @rental_request = CatRentalRequest.new
+    # Grab the cat_id from params if it exists. 
+    # If it doesn't exist, :cat_id will still be nil.
+    @rental_request.cat_id = params[:cat_id] 
+  end
+
+  private
+
+  def current_cat_rental_request
+    @rental_request ||=
+      CatRentalRequest.includes(:cat).find(params[:id])
+  end
+
+  def current_cat
+    current_cat_rental_request.cat
+  end
+
+  def require_cat_ownership
+    redirect_to cat_url(current_cat) unless current_user.owns_cat?(current_cat)
+  end
+
+  def cat_rental_request_params
+    params.require(:cat_rental_request).permit(:cat_id, :end_date, :start_date, :status)
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/controllers/cats_controller.rb b/rails/homeworks/helpers-layouts-mailer/app/controllers/cats_controller.rb
new file mode 100644
index 0000000..64151e6
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/controllers/cats_controller.rb
@@ -0,0 +1,54 @@
+class CatsController < ApplicationController
+  before_action :require_cat_ownership, only: %i(edit update)
+  before_action :require_logged_in, only: %i(new create)
+
+  def index
+    @cats = Cat.all
+    render :index
+  end
+
+  def show
+    @cat = Cat.find(params[:id])
+    render :show
+  end
+
+  def new
+    @cat = Cat.new
+    render :new
+  end
+
+  def create
+    @cat = Cat.new(cat_params)
+    @cat.owner = current_user
+    if @cat.save
+      redirect_to cat_url(@cat)
+    else
+      flash.now[:errors] = @cat.errors.full_messages
+      render :new
+    end
+  end
+
+  def edit
+    render :edit
+  end
+
+  def update
+    if @cat.update(cat_params)
+      redirect_to cat_url(@cat)
+    else
+      flash.now[:errors] = @cat.errors.full_messages
+      render :edit
+    end
+  end
+
+  private
+
+  def cat_params
+    params.require(:cat).permit(:birth_date, :color, :description, :name, :sex)
+  end
+
+  def require_cat_ownership
+    @cat = current_user&.cats&.find_by(id: params[:id])
+    redirect_to cats_url unless @cat
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/controllers/concerns/.keep b/rails/homeworks/helpers-layouts-mailer/app/controllers/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/app/controllers/sessions_controller.rb b/rails/homeworks/helpers-layouts-mailer/app/controllers/sessions_controller.rb
new file mode 100644
index 0000000..20c784e
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/controllers/sessions_controller.rb
@@ -0,0 +1,26 @@
+class SessionsController < ApplicationController
+  before_action :require_logged_out, only: %i(create new)
+
+  def create
+    user = User.find_by_credentials(
+      params[:user][:username],
+      params[:user][:password]
+    )
+
+    if user.nil?
+      flash.now[:errors] = ["Incorrect username and/or password"]
+      render :new
+    else
+      login!(user)
+      redirect_to cats_url
+    end
+  end
+
+  def destroy
+    logout!
+    redirect_to new_session_url
+  end
+
+  def new
+  end
+end
diff --git a/rails/homeworks/helpers-layouts-mailer/app/controllers/users_controller.rb b/rails/homeworks/helpers-layouts-mailer/app/controllers/users_controller.rb
new file mode 100644
index 0000000..1cbb591
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/controllers/users_controller.rb
@@ -0,0 +1,24 @@
+class UsersController < ApplicationController
+  before_action :require_logged_out
+
+  def create
+    @user = User.new(user_params)
+    if @user.save
+      login!(@user)
+      redirect_to cats_url
+    else
+      flash.now[:errors] = @user.errors.full_messages
+      render :new
+    end
+  end
+
+  def new
+    @user = User.new
+  end
+
+  private
+
+  def user_params
+    params.require(:user).permit(:password, :username)
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/helpers/application_helper.rb b/rails/homeworks/helpers-layouts-mailer/app/helpers/application_helper.rb
new file mode 100644
index 0000000..71128bb
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/helpers/application_helper.rb
@@ -0,0 +1,9 @@
+module ApplicationHelper
+  def auth_token
+    "<input
+      type='hidden'
+      name='authenticity_token'
+      value='#{form_authenticity_token}'
+    />".html_safe
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/models/application_record.rb b/rails/homeworks/helpers-layouts-mailer/app/models/application_record.rb
new file mode 100644
index 0000000..b63caeb
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/models/application_record.rb
@@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+  primary_abstract_class
+end
diff --git a/rails/homeworks/helpers-layouts-mailer/app/models/cat.rb b/rails/homeworks/helpers-layouts-mailer/app/models/cat.rb
new file mode 100644
index 0000000..7dcf086
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/models/cat.rb
@@ -0,0 +1,51 @@
+# == Schema Information
+#
+# Table name: cats
+#
+#  id          :bigint           not null, primary key
+#  birth_date  :date             not null
+#  color       :string           not null
+#  name        :string           not null
+#  sex         :string(1)        not null
+#  description :text
+#  created_at  :datetime         not null
+#  updated_at  :datetime         not null
+#  owner_id    :bigint           not null
+#
+require 'action_view'
+
+class Cat < ApplicationRecord
+  include ActionView::Helpers::DateHelper
+
+  # .freeze renders a constant immutable.
+  CAT_COLORS = %w[black white orange brown].freeze
+
+  validates :color, inclusion: CAT_COLORS
+  validates :sex, inclusion: %w[M F]
+  # Note that you don't need to validate `color` or `sex` for presence because
+  # NULL values for those columns will fail the inclusion tests.
+  validates :birth_date, :name, presence: true
+  validate :birth_date_cannot_be_future
+
+  # Remember: `belongs_to` and `has_many` are just methods where the first
+  # argument is the name of the association and the second argument is an
+  # options hash.
+  belongs_to :owner,
+    class_name: 'User'
+
+  has_many :rental_requests,
+    class_name: :CatRentalRequest,
+    dependent: :destroy
+
+  def birth_date_cannot_be_future
+    # Must check that birth_date is present because `>` will crash if run on
+    # `nil`
+    return unless birth_date.present? && birth_date > Date.today
+
+    errors.add(:birth_date, "can't be in the future")
+  end
+
+  def age
+    time_ago_in_words(birth_date)
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/models/cat_rental_request.rb b/rails/homeworks/helpers-layouts-mailer/app/models/cat_rental_request.rb
new file mode 100644
index 0000000..bd5edc0
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/models/cat_rental_request.rb
@@ -0,0 +1,161 @@
+# == Schema Information
+#
+# Table name: cat_rental_requests
+#
+#  id           :bigint           not null, primary key
+#  cat_id       :bigint           not null
+#  start_date   :date             not null
+#  end_date     :date             not null
+#  status       :string           default("PENDING"), not null
+#  created_at   :datetime         not null
+#  updated_at   :datetime         not null
+#  requester_id :bigint           not null
+#
+class CatRentalRequest < ApplicationRecord
+  # .freeze renders constants immutable
+  STATUS_STATES = %w[APPROVED DENIED PENDING].freeze
+
+  validates :status, inclusion: STATUS_STATES
+  # The `presence` of `status` is guaranteed if it is included in
+  # `STATUS_STATES`; no need to check for it again.
+  validates :end_date, :start_date, presence: true
+  validate :start_must_come_before_end
+  validate :does_not_overlap_approved_request
+
+  belongs_to :cat
+  belongs_to :requester,
+    class_name: :User
+
+  after_initialize :assign_pending_status
+
+  def approve!
+    raise 'not pending' unless self.status == 'PENDING'
+
+    transaction do
+      self.status = 'APPROVED'
+      self.save!
+
+      # When you approve this request, you reject all other overlapping
+      # requests for this cat.
+      overlapping_pending_requests.each do |req|
+        req.update!(status: 'DENIED')
+      end
+    end
+  end
+
+  def approved?
+    self.status == 'APPROVED'
+  end
+
+  def denied?
+    self.status == 'DENIED'
+  end
+
+  def deny!
+    self.status = 'DENIED'
+    self.save!
+  end
+
+  def pending?
+    self.status == 'PENDING'
+  end
+
+  private
+
+  def assign_pending_status
+    self.status ||= 'PENDING'
+  end
+
+  def overlapping_requests
+    # ==========================================================================
+    #
+    # Ranges can overlap in several ways:
+    #
+    #   |-----|       |-----|     |---|
+    #       |-----|   |-----|   |-------|
+    #     (2x)                    (2x)
+    #
+    # ==========================================================================
+    #
+    # However, it is easier to think of the two cases where they do not overlap:
+    #
+    #    [Case 1]
+    #
+    #        A              B
+    #    |-------|      |-------|
+    #    A(s)    A(e)   B(s)    B(e)
+    #
+    # The start point of B comes after the end point of A. Thus: B(s) > A(e)
+    #
+    #
+    #    [Case 2]
+    #
+    #        B              A
+    #    |-------|      |-------|
+    #    B(s)    B(e)   A(s)    A(e)
+    #
+    # The start point of A comes after the end point of B. Thus: A(s) > B(e)
+    #
+    # ==========================================================================
+    #
+    # Taking those two cases, you can say there's no overlap when:
+    #
+    #   B(s) > A(e) || A(s) > B(e)
+    #
+    # ==========================================================================
+    #
+    # You can negate this to get all cases where there must be overlap:
+    #
+    #   !( B(s) > A(e) || A(s) > B(e) )
+    #
+    # In order for overlap to occur, the other range cannot be entirely before
+    # it or entirely after it.
+    #
+    # ==========================================================================
+    #
+    # You could distribute the negation:
+    #
+    #   !( B(s) > A(e) ) && !( A(s) > B(e) )
+    #
+    # And take it even further, making it shorter, but perhaps less intuitive:
+    #
+    #   B(s) <= A(e) && A(s) <= B(e)
+    #
+    # ==========================================================================
+
+    # You want:
+    # 1. A different request
+    # 2. That is for the same cat.
+    # 3. That overlaps.
+
+    CatRentalRequest
+      .where.not(id: self.id)
+      .where(cat_id: cat_id)
+      .where.not('start_date > :end_date OR end_date < :start_date',
+                 start_date: start_date, end_date: end_date)
+  end
+
+  def overlapping_approved_requests
+    overlapping_requests.where('status = \'APPROVED\'')
+  end
+
+  def overlapping_pending_requests
+    overlapping_requests.where('status = \'PENDING\'')
+  end
+
+  def does_not_overlap_approved_request
+    # A denied request doesn't need to be checked. A pending request
+    # should be checked; users shouldn't be able to make requests for
+    # periods during which a cat has already been spoken for.
+    return if self.denied? || overlapping_approved_requests.empty?
+
+    errors.add(:base, 'Request conflicts with existing approved request')
+  end
+
+  def start_must_come_before_end
+    return if start_date < end_date
+
+    errors.add(:start_date, 'must come before end date')
+    errors.add(:end_date, 'must come after start date')
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/models/concerns/.keep b/rails/homeworks/helpers-layouts-mailer/app/models/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/app/models/user.rb b/rails/homeworks/helpers-layouts-mailer/app/models/user.rb
new file mode 100644
index 0000000..de239f5
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/models/user.rb
@@ -0,0 +1,75 @@
+# == Schema Information
+#
+# Table name: users
+#
+#  id              :bigint           not null, primary key
+#  username        :string           not null
+#  password_digest :string           not null
+#  session_token   :string           not null
+#  created_at      :datetime         not null
+#  updated_at      :datetime         not null
+#
+class User < ApplicationRecord
+  validates :username, :session_token, presence: true, uniqueness: true
+  validates :password_digest, presence: true
+  # If a password was set, validate that it meets the requirements.
+  # Note the `allow_nil`.
+  validates :password, length: { minimum: 6, allow_nil: true }
+
+  before_validation :ensure_session_token
+
+  attr_reader :password
+
+  # Remember: `has_many` is just a method where the first argument is the name
+  # of the association and the second argument is an options hash.
+  has_many :cats,
+    foreign_key: :owner_id,
+    dependent: :destroy,
+    inverse_of: :owner
+
+  has_many :cat_rental_requests,
+    foreign_key: :requester_id,
+    dependent: :destroy,
+    inverse_of: :requester
+
+  def self.find_by_credentials(username, password)
+    user = User.find_by(username: username)
+    # `user&.is_password?(password)` is syntactic sugar for
+    # `user && user.is_password?(password)`
+    user&.is_password?(password) ? user : nil
+  end
+
+  def is_password?(password)
+    BCrypt::Password.new(self.password_digest).is_password?(password)
+  end
+
+  def password=(password)
+    @password = password
+    self.password_digest = BCrypt::Password.create(password)
+  end
+
+  def reset_session_token!
+    self.session_token = generate_unique_session_token
+    self.save!
+    self.session_token
+  end
+
+  def owns_cat?(cat)
+    cat.owner == self
+  end
+
+  private
+
+  def generate_unique_session_token
+    # `SecureRandom::urlsafe_base64` does not guarantee uniqueness. Wrapping
+    # this call in a loop ensures that no other user has the generated token.
+    loop do
+      session_token = SecureRandom::urlsafe_base64(16)
+      return session_token unless User.exists?(session_token: session_token)
+    end
+  end
+
+  def ensure_session_token
+    self.session_token ||= generate_unique_session_token
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/cat_rental_requests/new.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/cat_rental_requests/new.html.erb
new file mode 100644
index 0000000..29417f8
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/cat_rental_requests/new.html.erb
@@ -0,0 +1,48 @@
+<section class="page"><div class="centered-box">
+  <h1>Create Rental Request</h1>
+
+  <%= render "shared/errors" %>
+
+  <form action="<%= cat_rental_requests_url %>" method="post">
+    <input
+      type="hidden"
+      name="authenticity_token"
+      value="<%= form_authenticity_token %>"
+    >
+
+    <label for="cat_rental_request_cat_id">Cat</label>
+    <select name="cat_rental_request[cat_id]"
+            id="cat_rental_request_cat_id"
+            required>
+      <option selected disabled>--Select Cat--</option>
+      <% Cat.all.each do |cat| %>
+        <% selected = @rental_request.cat_id == cat.id %>
+        <option <%= selected ? "selected" : "" %>
+                value="<%= cat.id %>">
+          <%= cat.name %>
+        </option>
+      <% end %>
+    </select>
+    <br>
+
+    <label for="cat_rental_request_start_date">Start Date</label>
+    <input
+      type="date"
+      name="cat_rental_request[start_date]"
+      value="<%= @rental_request.start_date %>"
+      id="cat_rental_request_start_date"
+      required>
+    <br>
+
+    <label for="cat_rental_request_end_date">End Date</label>
+    <input
+      type="date"
+      name="cat_rental_request[end_date]"
+      value="<%= @rental_request.end_date %>"
+      id="cat_rental_request_end_date"
+      required>
+    <br>
+
+    <input type="submit" value="Submit">
+  </form>
+</div></section>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/cats/_form.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/cats/_form.html.erb
new file mode 100644
index 0000000..6d54860
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/cats/_form.html.erb
@@ -0,0 +1,69 @@
+<% action = (cat.persisted? ? cat_url(cat) : cats_url) %>
+<% method = (cat.persisted? ? :PATCH : :POST) %>
+
+<form action="<%= action %>" method="POST">
+  <input type="hidden" name="_method" value="<%= method %>">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>"
+  >
+
+  <label for="cat_name">Name</label>
+  <input
+    type="text"
+    name="cat[name]"
+    id="cat_name"
+    value="<%= cat.name %>"
+  >
+  <br>
+
+  <label for="cat_birth_date">Birth date</label>
+  <input
+    type="date"
+    name="cat[birth_date]"
+    id="cat_birth_date"
+    value="<%= cat.birth_date %>"
+  >
+  <br>
+
+  <label for="cat_color">Color</label>
+  <select name="cat[color]" id="cat_color">
+    <option disabled selected>-- select a color --</option>
+      <% Cat::CAT_COLORS.each do |color| %>
+        <option
+          <%= cat.color == color ? "selected" : "" %>
+          value="<%= color %>">
+          <%= color.upcase %>
+        </option>
+      <% end %>
+  </select>
+  <br>
+
+  <input
+    type="radio"
+    name="cat[sex]"
+    value="M"
+    id="cat_sex_male"
+    <%= cat.sex == "M" ? "checked" : "" %>
+  >
+  <label for="cat_sex_male">Male</label>
+  <input
+    type="radio"
+    name="cat[sex]"
+    value="F"
+    id="cat_sex_female"
+    <%= cat.sex == "F" ? "checked" : "" %>
+  >
+  <label for="cat_sex_female">Female</label>
+  <br>
+
+  <label>
+    Description
+    <textarea name="cat[description]"><%= cat.description %></textarea>
+  </label>
+
+  <br>
+  <% submit_text = (cat.persisted? ? 'Update' : 'Create') + ' cat!' %>
+  <input type="submit" value="<%= submit_text %>">
+</form>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/cats/_req_tr.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/cats/_req_tr.html.erb
new file mode 100644
index 0000000..6018e78
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/cats/_req_tr.html.erb
@@ -0,0 +1,29 @@
+<% is_cat_owner = current_user && current_user.owns_cat?(@cat) %>
+
+<tr>
+  <td><%= req.requester.username %></td>
+  <td><%= req.start_date %></td>
+  <td><%= req.end_date %></td>
+  <td>
+    <% if req.pending? && is_cat_owner %>
+      <form action="<%= approve_cat_rental_request_url(req) %>" method="post">
+        <input
+          type="hidden"
+          name="authenticity_token"
+          value="<%= form_authenticity_token %>"
+        >
+        <input type="submit" value="Approve">
+      </form>
+      <form action="<%= deny_cat_rental_request_url(req) %>" method="post">
+        <input
+          type="hidden"
+          name="authenticity_token"
+          value="<%= form_authenticity_token %>"
+        >
+        <input type="submit" value="Deny">
+      </form>
+    <% else %>
+      <%= req.status %>
+    <% end %>
+  </td>
+</tr>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/cats/edit.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/cats/edit.html.erb
new file mode 100644
index 0000000..3df7fa1
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/cats/edit.html.erb
@@ -0,0 +1,5 @@
+<section class="page"><div class="centered-box">
+  <h1>Edit My Cat</h1>
+  <%= render 'shared/errors' %>
+  <%= render 'form', cat: @cat %>
+</div></section>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/cats/index.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/cats/index.html.erb
new file mode 100644
index 0000000..ea40a5e
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/cats/index.html.erb
@@ -0,0 +1,23 @@
+<section class="cat-index-holder">
+  <nav>
+    <h1>ALL THE CATS IN THE WORLD</h1>
+    <a href="<%= new_cat_url %>">
+      Add Cat
+      <i class="fa fa-plus" aria-hidden="true"></i>
+    </a>
+    <a href="<%= new_cat_rental_request_url %>">
+      Request a Rental
+      <i class="fa fa-plus" aria-hidden="true"></i>
+    </a>
+  </nav>
+  <section class="cat-index">
+    <% @cats.each do |cat| %>
+      <div class="cat-index-item">
+        <div>
+          <img src="http://placekitten.com/g/231/231" >
+          <br /><a href="<%= cat_url(cat) %>">Rent <%= cat.name %></a>
+        </div>
+      </div>
+    <% end %>
+  </section>
+</section>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/cats/new.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/cats/new.html.erb
new file mode 100644
index 0000000..dc96069
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/cats/new.html.erb
@@ -0,0 +1,5 @@
+<section class="page"><div class="centered-box">
+  <h1>New Cat</h1>
+  <%= render 'shared/errors' %>
+  <%= render 'form', cat: @cat %>
+</div></section>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/cats/show.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/cats/show.html.erb
new file mode 100644
index 0000000..ec0acde
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/cats/show.html.erb
@@ -0,0 +1,52 @@
+<section class="page"><div class="centered-box">
+  <img src="http://placekitten.com/g/300/300" >
+  <h1><%= @cat.name %></h1>
+
+  <table>
+    <tr>
+      <th>Attribute</th>
+      <th>Value</th>
+    </tr>
+    <% [:age, :birth_date, :color, :sex].each do |attr_name| %>
+      <tr>
+        <td><%= attr_name %></td>
+        <td><%= @cat.send(attr_name) %></td>
+      </tr>
+    <% end %>
+    <% if @cat.description.present? %>
+      <tr>
+        <th colspan="2">Description</th>
+      </tr>
+      <tr>
+        <td colspan="2"><%= @cat.description %></td>
+      </tr>
+    <% end %>
+  </table>
+
+  <% if @cat.owner == current_user %>
+    <a href="<%= edit_cat_url(@cat) %>">Edit <%= @cat.name %></a>
+  <% end %>
+
+  <br><br>
+  <h1>Rental Requests</h1>
+  <% if @cat.rental_requests.empty? %>
+    <p><%= @cat.name %> has no rental requests.</p>
+  <% else %>
+    <table>
+      <tr>
+        <th>User</th>
+        <th>Start Date</th>
+        <th>End Date</th>
+        <th>Status</th>
+      </tr>
+      <% @cat.rental_requests.includes(:requester).order('start_date').each do |req| %>
+        <%= render 'req_tr', req: req %>
+      <% end %>
+    </table>
+  <% end %>
+  <% if logged_in? %>
+    <a href="<%= new_cat_cat_rental_request_url(@cat) %>">
+      Request a Rental
+    </a>  
+  <% end %>
+</div></section>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/layouts/application.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/layouts/application.html.erb
new file mode 100644
index 0000000..9595a39
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/layouts/application.html.erb
@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>99 Cats</title>
+    <link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" integrity="sha384-wvfXpqpZZVQGK6TAh5PVlGOfQNHSoD2xbE+QkPxCAFlNEevoEH3Sl0sibVcOQVnN" crossorigin="anonymous">
+    <link href="https://fonts.googleapis.com/css?family=Amatic+SC:400,700" rel="stylesheet">
+    <meta name="viewport" content="width=device-width,initial-scale=1">
+    <%= csrf_meta_tags %>
+    <%= csp_meta_tag %>
+
+    <%= stylesheet_link_tag "application" %>
+  </head>
+
+  <body>
+    <nav class="main-nav">
+      <h1><a href="<%= cats_url %>">99 Cats</a></h1>
+      <div>
+        <% if current_user.nil? %>
+          <a href="<%= new_session_url %>">Sign in</a>
+          <a href="<%= new_user_url %>">Sign up</a>
+        <% else %>
+          <%= current_user.username %>
+          <form action="<%= session_url %>" method="post">
+            <input
+              type="hidden"
+              name="authenticity_token"
+              value="<%= form_authenticity_token %>"
+            >
+            <input type="hidden" name="_method" value="delete">
+            <input type="submit" value="Logout">
+          </form>
+        <% end %>
+      </div>
+    </nav>
+    <main>
+      <%= yield %>
+    </main>
+  </body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/sessions/new.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/sessions/new.html.erb
new file mode 100644
index 0000000..aa7dc8a
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/sessions/new.html.erb
@@ -0,0 +1,23 @@
+<section class="page"><div class="centered-box">
+    <h1>Sign in</h1>
+
+      <%= render "shared/errors" %>
+
+    <form action="<%= session_url %>" method="post">
+      <input
+        type="hidden"
+        name="authenticity_token"
+        value="<%= form_authenticity_token %>"
+      >
+
+      <label for="user_username">Username: </label>
+      <input type="text" name="user[username]" id="user_username">
+      <br>
+
+      <label for="user_password">Password: </label>
+      <input type="password" name="user[password]" id="user_password">
+      <br>
+
+      <input type="submit" value="Sign in">
+    </form>
+</div></section>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/shared/_errors.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/shared/_errors.html.erb
new file mode 100644
index 0000000..71eb920
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/shared/_errors.html.erb
@@ -0,0 +1,7 @@
+<% if flash[:errors] %>
+  <ul>
+  <% flash[:errors].each do |error| %>
+    <li><%= error %></li>
+  <% end %>
+  </ul>
+<% end %>
diff --git a/rails/homeworks/helpers-layouts-mailer/app/views/users/new.html.erb b/rails/homeworks/helpers-layouts-mailer/app/views/users/new.html.erb
new file mode 100644
index 0000000..25ec4e5
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/app/views/users/new.html.erb
@@ -0,0 +1,31 @@
+<section class="page">
+  <div class="centered-box">
+    <h1>New User</h1>
+
+    <%= render 'shared/errors' %>
+
+    <form action="<%= users_url %>" method="post">
+      <input
+        type="hidden"
+        name="authenticity_token"
+        value="<%= form_authenticity_token %>"
+      >
+
+      <label for="user_username">Username: </label>
+      <input type="text"
+        name="user[username]"
+        id="user_username"
+        value="<%= @user.username %>">
+      <br>
+
+      <label for="user_password">Password: </label>
+      <input type="password"
+        name="user[password]"
+        id="user_password"
+        value="<%= @user.password %>">
+      <br>
+
+      <input type="submit" value="Sign up!">
+    </form>
+  </div>
+</section>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/bin/bundle b/rails/homeworks/helpers-layouts-mailer/bin/bundle
new file mode 100644
index 0000000..15f37e3
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/bin/bundle
@@ -0,0 +1,114 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'bundle' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "rubygems"
+
+m = Module.new do
+  module_function
+
+  def invoked_as_script?
+    File.expand_path($0) == File.expand_path(__FILE__)
+  end
+
+  def env_var_version
+    ENV["BUNDLER_VERSION"]
+  end
+
+  def cli_arg_version
+    return unless invoked_as_script? # don't want to hijack other binstubs
+    return unless "update".start_with?(ARGV.first || " ") # must be running `bundle update`
+    bundler_version = nil
+    update_index = nil
+    ARGV.each_with_index do |a, i|
+      if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
+        bundler_version = a
+      end
+      next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
+      bundler_version = $1
+      update_index = i
+    end
+    bundler_version
+  end
+
+  def gemfile
+    gemfile = ENV["BUNDLE_GEMFILE"]
+    return gemfile if gemfile && !gemfile.empty?
+
+    File.expand_path("../../Gemfile", __FILE__)
+  end
+
+  def lockfile
+    lockfile =
+      case File.basename(gemfile)
+      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
+      else "#{gemfile}.lock"
+      end
+    File.expand_path(lockfile)
+  end
+
+  def lockfile_version
+    return unless File.file?(lockfile)
+    lockfile_contents = File.read(lockfile)
+    return unless lockfile_contents =~ /\n\nBUNDLED WITH\n\s{2,}(#{Gem::Version::VERSION_PATTERN})\n/
+    Regexp.last_match(1)
+  end
+
+  def bundler_requirement
+    @bundler_requirement ||=
+      env_var_version || cli_arg_version ||
+        bundler_requirement_for(lockfile_version)
+  end
+
+  def bundler_requirement_for(version)
+    return "#{Gem::Requirement.default}.a" unless version
+
+    bundler_gem_version = Gem::Version.new(version)
+
+    requirement = bundler_gem_version.approximate_recommendation
+
+    return requirement unless Gem.rubygems_version < Gem::Version.new("2.7.0")
+
+    requirement += ".a" if bundler_gem_version.prerelease?
+
+    requirement
+  end
+
+  def load_bundler!
+    ENV["BUNDLE_GEMFILE"] ||= gemfile
+
+    activate_bundler
+  end
+
+  def activate_bundler
+    gem_error = activation_error_handling do
+      gem "bundler", bundler_requirement
+    end
+    return if gem_error.nil?
+    require_error = activation_error_handling do
+      require "bundler/version"
+    end
+    return if require_error.nil? && Gem::Requirement.new(bundler_requirement).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+    warn "Activating bundler (#{bundler_requirement}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_requirement}'`"
+    exit 42
+  end
+
+  def activation_error_handling
+    yield
+    nil
+  rescue StandardError, LoadError => e
+    e
+  end
+end
+
+m.load_bundler!
+
+if m.invoked_as_script?
+  load Gem.bin_path("bundler", "bundle")
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/bin/rails b/rails/homeworks/helpers-layouts-mailer/bin/rails
new file mode 100644
index 0000000..fa3c01a
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/bin/rails
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+APP_PATH = File.expand_path("../config/application", __dir__)
+require_relative "../config/boot"
+require "rails/commands"
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/bin/rake b/rails/homeworks/helpers-layouts-mailer/bin/rake
new file mode 100644
index 0000000..19d605d
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/bin/rake
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+require_relative "../config/boot"
+require "rake"
+Rake.application.run
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/bin/setup b/rails/homeworks/helpers-layouts-mailer/bin/setup
new file mode 100644
index 0000000..9bd670f
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/bin/setup
@@ -0,0 +1,33 @@
+#!/usr/bin/env ruby
+require "fileutils"
+
+# path to your application root.
+APP_ROOT = File.expand_path("..", __dir__)
+
+def system!(*args)
+  system(*args) || abort("\n== Command #{args} failed ==")
+end
+
+FileUtils.chdir APP_ROOT do
+  # This script is a way to set up or update your development environment automatically.
+  # This script is idempotent, so that you can run it at any time and get an expectable outcome.
+  # Add necessary setup steps to this file.
+
+  puts "== Installing dependencies =="
+  system! "gem install bundler --conservative"
+  system("bundle check") || system!("bundle install")
+
+  # puts "\n== Copying sample files =="
+  # unless File.exist?("config/database.yml")
+  #   FileUtils.cp "config/database.yml.sample", "config/database.yml"
+  # end
+
+  puts "\n== Preparing database =="
+  system! "bin/rails db:prepare"
+
+  puts "\n== Removing old logs and tempfiles =="
+  system! "bin/rails log:clear tmp:clear"
+
+  puts "\n== Restarting application server =="
+  system! "bin/rails restart"
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config.ru b/rails/homeworks/helpers-layouts-mailer/config.ru
new file mode 100644
index 0000000..38cc27a
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config.ru
@@ -0,0 +1,6 @@
+# This file is used by Rack-based servers to start the application.
+
+require_relative "config/environment"
+
+run Rails.application
+Rails.application.load_server
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/application.rb b/rails/homeworks/helpers-layouts-mailer/config/application.rb
new file mode 100644
index 0000000..22b7aac
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/application.rb
@@ -0,0 +1,38 @@
+require_relative "boot"
+
+require "rails"
+# Pick the frameworks you want:
+require "active_model/railtie"
+# require "active_job/railtie"
+require "active_record/railtie"
+# require "active_storage/engine"
+require "action_controller/railtie"
+require "action_mailer/railtie"
+# require "action_mailbox/engine"
+# require "action_text/engine"
+require "action_view/railtie"
+# require "action_cable/engine"
+# require "rails/test_unit/railtie"
+
+# Require the gems listed in Gemfile, including any gems
+# you've limited to :test, :development, or :production.
+Bundler.require(*Rails.groups)
+
+module NinetyNineCats2LongPractice
+  class Application < Rails::Application
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults 7.0
+    
+    config.action_controller.default_protect_from_forgery = false
+    # Configuration for the application, engines, and railties goes here.
+    #
+    # These settings can be overridden in specific environments using the files
+    # in config/environments, which are processed later.
+    #
+    # config.time_zone = "Central Time (US & Canada)"
+    # config.eager_load_paths << Rails.root.join("extras")
+
+    # Don't generate system test files.
+    config.generators.system_tests = nil
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/boot.rb b/rails/homeworks/helpers-layouts-mailer/config/boot.rb
new file mode 100644
index 0000000..2820116
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/boot.rb
@@ -0,0 +1,3 @@
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+
+require "bundler/setup" # Set up gems listed in the Gemfile.
diff --git a/rails/homeworks/helpers-layouts-mailer/config/credentials.yml.enc b/rails/homeworks/helpers-layouts-mailer/config/credentials.yml.enc
new file mode 100644
index 0000000..50395e9
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/credentials.yml.enc
@@ -0,0 +1 @@
+fO7L3PuH/eShQ0tYDhR0SutQiCF2sBx4ZZnspFWAd+OHOSo0bAo88xAhOMJBb4xmltZ6ZRnsddCwc0XQAHn7B6vphQRpGyrxlr6sEvATr3SbmQL6gtYHn353WtUe+swxTRMJ4Uqp2AYtI9fI4WUdAJzA+7UOwSipabDTQKVnpbzlNOgOkIfYGAQ/y1wq5WkRmUrUyOiUz/Qh6Tgd8v4mT9Fcwd9uj7uzmkNC9405KUuS1GEiwnH5Zw7UPGI7VcrQ2sDpmUSYjciZo/eXVOmLQ3lVlJgj7my5FuAEudohh2Vzi2pIc1zP3JJj/NPywzEXfJVP+EqVyZsPAr9JbFK4FPKDxgG2UFmHaSo7nzWzh4XVtLMokZZdifYNTjSOvkc2VQVHQ+nN/zdKt+F/qmUlA6G3mYT/DTmpFz0z--uGSYIi1SQxIBvTVO--iJrSV/vzB/VjM2MMbTpwxQ==
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/database.yml b/rails/homeworks/helpers-layouts-mailer/config/database.yml
new file mode 100644
index 0000000..2a43b14
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/database.yml
@@ -0,0 +1,86 @@
+# PostgreSQL. Versions 9.3 and up are supported.
+#
+# Install the pg driver:
+#   gem install pg
+# On macOS with Homebrew:
+#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
+# On macOS with MacPorts:
+#   gem install pg -- --with-pg-config=/opt/local/lib/postgresql84/bin/pg_config
+# On Windows:
+#   gem install pg
+#       Choose the win32 build.
+#       Install PostgreSQL and put its /bin directory on your path.
+#
+# Configure Using Gemfile
+# gem "pg"
+#
+default: &default
+  adapter: postgresql
+  encoding: unicode
+  # For details on connection pooling, see Rails configuration guide
+  # https://guides.rubyonrails.org/configuring.html#database-pooling
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+
+development:
+  <<: *default
+  database: ninety_nine_cats2_long_practice_development
+
+  # The specified database role being used to connect to postgres.
+  # To create additional roles in postgres see `$ createuser --help`.
+  # When left blank, postgres will use the default role. This is
+  # the same name as the operating system user running Rails.
+  #username: ninety_nine_cats2_long_practice
+
+  # The password associated with the postgres role (username).
+  #password:
+
+  # Connect on a TCP socket. Omitted by default since the client uses a
+  # domain socket that doesn't need configuration. Windows does not have
+  # domain sockets, so uncomment these lines.
+  #host: localhost
+
+  # The TCP port the server listens on. Defaults to 5432.
+  # If your server runs on a different port number, change accordingly.
+  #port: 5432
+
+  # Schema search path. The server defaults to $user,public
+  #schema_search_path: myapp,sharedapp,public
+
+  # Minimum log levels, in increasing order:
+  #   debug5, debug4, debug3, debug2, debug1,
+  #   log, notice, warning, error, fatal, and panic
+  # Defaults to warning.
+  #min_messages: notice
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: ninety_nine_cats2_long_practice_test
+
+# As with config/credentials.yml, you never want to store sensitive information,
+# like your database password, in your source code. If your source code is
+# ever seen by anyone, they now have access to your database.
+#
+# Instead, provide the password or a full connection URL as an environment
+# variable when you boot the app. For example:
+#
+#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
+#
+# If the connection URL is provided in the special DATABASE_URL environment
+# variable, Rails will automatically merge its configuration values on top of
+# the values provided in this file. Alternatively, you can specify a connection
+# URL environment variable explicitly:
+#
+#   production:
+#     url: <%= ENV["MY_APP_DATABASE_URL"] %>
+#
+# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
+# for a full overview on how database connection configuration can be specified.
+#
+production:
+  <<: *default
+  database: ninety_nine_cats2_long_practice_production
+  username: ninety_nine_cats2_long_practice
+  password: <%= ENV["NINETY_NINE_CATS2_LONG_PRACTICE_DATABASE_PASSWORD"] %>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/environment.rb b/rails/homeworks/helpers-layouts-mailer/config/environment.rb
new file mode 100644
index 0000000..445c788
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/environment.rb
@@ -0,0 +1,5 @@
+# Load the Rails application.
+require_relative "application"
+
+# Initialize the Rails application.
+Rails.application.initialize!
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/environments/development.rb b/rails/homeworks/helpers-layouts-mailer/config/environments/development.rb
new file mode 100644
index 0000000..851adc5
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/environments/development.rb
@@ -0,0 +1,62 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # In the development environment your application's code is reloaded any time
+  # it changes. This slows down response time but is perfect for development
+  # since you don't have to restart the web server when you make code changes.
+  config.cache_classes = false
+
+  # Do not eager load code on boot.
+  config.eager_load = false
+
+  # Show full error reports.
+  config.consider_all_requests_local = true
+
+  # Enable server timing
+  config.server_timing = true
+
+  # Enable/disable caching. By default caching is disabled.
+  # Run rails dev:cache to toggle caching.
+  if Rails.root.join("tmp/caching-dev.txt").exist?
+    config.action_controller.perform_caching = true
+    config.action_controller.enable_fragment_cache_logging = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      "Cache-Control" => "public, max-age=#{2.days.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
+
+  # Print deprecation notices to the Rails logger.
+  config.active_support.deprecation = :log
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raise an error on page load if there are pending migrations.
+  config.active_record.migration_error = :page_load
+
+  # Highlight code that triggered database queries in logs.
+  config.active_record.verbose_query_logs = true
+
+  # Suppress logger output for asset requests.
+  config.assets.quiet = true
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+
+  # Uncomment if you wish to allow Action Cable access from any origin.
+  # config.action_cable.disable_request_forgery_protection = true
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/environments/production.rb b/rails/homeworks/helpers-layouts-mailer/config/environments/production.rb
new file mode 100644
index 0000000..6aee001
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/environments/production.rb
@@ -0,0 +1,75 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Code is not reloaded between requests.
+  config.cache_classes = true
+
+  # Eager load code on boot. This eager loads most of Rails and
+  # your application in memory, allowing both threaded web servers
+  # and those relying on copy on write to perform better.
+  # Rake tasks automatically ignore this option for performance.
+  config.eager_load = true
+
+  # Full error reports are disabled and caching is turned on.
+  config.consider_all_requests_local       = false
+  config.action_controller.perform_caching = true
+
+  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  # config.require_master_key = true
+
+  # Disable serving static files from the `/public` folder by default since
+  # Apache or NGINX already handles this.
+  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
+
+  # Compress CSS using a preprocessor.
+  # config.assets.css_compressor = :sass
+
+  # Do not fallback to assets pipeline if a precompiled asset is missed.
+  config.assets.compile = false
+
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.asset_host = "http://assets.example.com"
+
+  # Specifies the header that your server uses for sending files.
+  # config.action_dispatch.x_sendfile_header = "X-Sendfile" # for Apache
+  # config.action_dispatch.x_sendfile_header = "X-Accel-Redirect" # for NGINX
+
+  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
+  # config.force_ssl = true
+
+  # Include generic and useful information about system operation, but avoid logging too much
+  # information to avoid inadvertent exposure of personally identifiable information (PII).
+  config.log_level = :info
+
+  # Prepend all log lines with the following tags.
+  config.log_tags = [ :request_id ]
+
+  # Use a different cache store in production.
+  # config.cache_store = :mem_cache_store
+
+  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
+  # the I18n.default_locale when a translation cannot be found).
+  config.i18n.fallbacks = true
+
+  # Don't log any deprecations.
+  config.active_support.report_deprecations = false
+
+  # Use default logging formatter so that PID and timestamp are not suppressed.
+  config.log_formatter = ::Logger::Formatter.new
+
+  # Use a different logger for distributed setups.
+  # require "syslog/logger"
+  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
+
+  if ENV["RAILS_LOG_TO_STDOUT"].present?
+    logger           = ActiveSupport::Logger.new(STDOUT)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/environments/test.rb b/rails/homeworks/helpers-layouts-mailer/config/environments/test.rb
new file mode 100644
index 0000000..da62dfc
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/environments/test.rb
@@ -0,0 +1,50 @@
+require "active_support/core_ext/integer/time"
+
+# The test environment is used exclusively to run your application's
+# test suite. You never need to work with it otherwise. Remember that
+# your test database is "scratch space" for the test suite and is wiped
+# and recreated between test runs. Don't rely on the data there!
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Turn false under Spring and add config.action_view.cache_template_loading = true.
+  config.cache_classes = true
+
+  # Eager loading loads your whole application. When running a single test locally,
+  # this probably isn't necessary. It's a good idea to do in a continuous integration
+  # system, or in some way before deploying your code.
+  config.eager_load = ENV["CI"].present?
+
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = {
+    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
+  }
+
+  # Show full error reports and disable caching.
+  config.consider_all_requests_local       = true
+  config.action_controller.perform_caching = false
+  config.cache_store = :null_store
+
+  # Raise exceptions instead of rendering exception templates.
+  config.action_dispatch.show_exceptions = false
+
+  # Disable request forgery protection in test environment.
+  config.action_controller.allow_forgery_protection = false
+
+  # Print deprecation notices to the stderr.
+  config.active_support.deprecation = :stderr
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/initializers/assets.rb b/rails/homeworks/helpers-layouts-mailer/config/initializers/assets.rb
new file mode 100644
index 0000000..bd8332f
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/initializers/assets.rb
@@ -0,0 +1,12 @@
+# Be sure to restart your server when you modify this file.
+
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = "1.0"
+
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/initializers/content_security_policy.rb b/rails/homeworks/helpers-layouts-mailer/config/initializers/content_security_policy.rb
new file mode 100644
index 0000000..d9b954b
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/initializers/content_security_policy.rb
@@ -0,0 +1,26 @@
+# Be sure to restart your server when you modify this file.
+
+# Define an application-wide content security policy
+# For further information see the following documentation
+# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
+
+# Rails.application.configure do
+#   config.content_security_policy do |policy|
+#     policy.default_src :self, :https
+#     policy.font_src    :self, :https, :data
+#     policy.img_src     :self, :https, :data
+#     policy.object_src  :none
+#     policy.script_src  :self, :https
+#     policy.style_src   :self, :https
+#     # Specify URI for violation reports
+#     # policy.report_uri "/csp-violation-report-endpoint"
+#   end
+#
+#   # Generate session nonces for permitted importmap and inline scripts
+#   config.content_security_policy_nonce_generator = ->(request) { request.session.id.to_s }
+#   config.content_security_policy_nonce_directives = %w(script-src)
+#
+#   # Report CSP violations to a specified URI. See:
+#   # https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy-Report-Only
+#   # config.content_security_policy_report_only = true
+# end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/initializers/filter_parameter_logging.rb b/rails/homeworks/helpers-layouts-mailer/config/initializers/filter_parameter_logging.rb
new file mode 100644
index 0000000..b4db5f6
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/initializers/filter_parameter_logging.rb
@@ -0,0 +1,8 @@
+# Be sure to restart your server when you modify this file.
+
+# Configure parameters to be filtered from the log file. Use this to limit dissemination of
+# sensitive information. See the ActiveSupport::ParameterFilter documentation for supported
+# notations and behaviors.
+Rails.application.config.filter_parameters += [
+  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
+]
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/initializers/inflections.rb b/rails/homeworks/helpers-layouts-mailer/config/initializers/inflections.rb
new file mode 100644
index 0000000..df431d7
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/initializers/inflections.rb
@@ -0,0 +1,16 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new inflection rules using the following format. Inflections
+# are locale specific, and you may define rules for as many different
+# locales as you wish. All of these examples are active by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.plural /^(ox)$/i, "\\1en"
+#   inflect.singular /^(ox)en/i, "\\1"
+#   inflect.irregular "person", "people"
+#   inflect.uncountable %w( fish sheep )
+# end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym "RESTful"
+# end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/initializers/permissions_policy.rb b/rails/homeworks/helpers-layouts-mailer/config/initializers/permissions_policy.rb
new file mode 100644
index 0000000..dd30019
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/initializers/permissions_policy.rb
@@ -0,0 +1,11 @@
+# Define an application-wide HTTP permissions policy. For further
+# information see https://developers.google.com/web/updates/2018/06/feature-policy
+#
+# Rails.application.config.permissions_policy do |f|
+#   f.camera      :none
+#   f.gyroscope   :none
+#   f.microphone  :none
+#   f.usb         :none
+#   f.fullscreen  :self
+#   f.payment     :self, "https://secure.example.com"
+# end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/locales/en.yml b/rails/homeworks/helpers-layouts-mailer/config/locales/en.yml
new file mode 100644
index 0000000..30c9973
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/locales/en.yml
@@ -0,0 +1,33 @@
+# Files in the config/locales directory are used for internationalization
+# and are automatically loaded by Rails. If you want to use locales other
+# than English, add the necessary files in this directory.
+#
+# To use the locales, use `I18n.t`:
+#
+#     I18n.t "hello"
+#
+# In views, this is aliased to just `t`:
+#
+#     <%= t("hello") %>
+#
+# To use a different locale, set it with `I18n.locale`:
+#
+#     I18n.locale = :es
+#
+# This would use the information in config/locales/es.yml.
+#
+# The following keys must be escaped otherwise they will not be retrieved by
+# the default I18n backend:
+#
+# true, false, on, off, yes, no
+#
+# Instead, surround them with single quotes.
+#
+# en:
+#   "true": "foo"
+#
+# To learn more, please read the Rails Internationalization guide
+# available at https://guides.rubyonrails.org/i18n.html.
+
+en:
+  hello: "Hello world"
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/puma.rb b/rails/homeworks/helpers-layouts-mailer/config/puma.rb
new file mode 100644
index 0000000..411b18d
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/puma.rb
@@ -0,0 +1,43 @@
+# Puma can serve each request in a thread from an internal thread pool.
+# The `threads` method setting takes two numbers: a minimum and maximum.
+# Any libraries that use thread pools should be configured to match
+# the maximum value specified for Puma. Default is set to 5 threads for minimum
+# and maximum; this matches the default thread size of Active Record.
+#
+max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
+min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count }
+threads min_threads_count, max_threads_count
+
+# Specifies the `worker_timeout` threshold that Puma will use to wait before
+# terminating a worker in development environments.
+#
+worker_timeout 3600 if ENV.fetch("RAILS_ENV", "development") == "development"
+
+# Specifies the `port` that Puma will listen on to receive requests; default is 3000.
+#
+port ENV.fetch("PORT") { 3000 }
+
+# Specifies the `environment` that Puma will run in.
+#
+environment ENV.fetch("RAILS_ENV") { "development" }
+
+# Specifies the `pidfile` that Puma will use.
+pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
+
+# Specifies the number of `workers` to boot in clustered mode.
+# Workers are forked web server processes. If using threads and workers together
+# the concurrency of the application would be max `threads` * `workers`.
+# Workers do not work on JRuby or Windows (both of which do not support
+# processes).
+#
+# workers ENV.fetch("WEB_CONCURRENCY") { 2 }
+
+# Use the `preload_app!` method when specifying a `workers` number.
+# This directive tells Puma to first boot the application and load code
+# before forking the application. This takes advantage of Copy On Write
+# process behavior so workers use less memory.
+#
+# preload_app!
+
+# Allow puma to be restarted by `bin/rails restart` command.
+plugin :tmp_restart
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/config/routes.rb b/rails/homeworks/helpers-layouts-mailer/config/routes.rb
new file mode 100644
index 0000000..f12c19f
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/config/routes.rb
@@ -0,0 +1,19 @@
+Rails.application.routes.draw do
+  # Define your application routes per the DSL in https://guides.rubyonrails.org/routing.html
+
+  # Defines the root path route ("/")
+  # root "articles#index"
+  root "cats#index"
+
+  resources :cats, except: :destroy do
+    resources :cat_rental_requests, only: [:new]
+  end
+  resources :cat_rental_requests, only: [:new, :create] do
+    member do
+      post :approve
+      post :deny
+    end
+  end
+  resource :session, only: [:new, :create, :destroy]
+  resources :users, only: [:new, :create]
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/db/migrate/20220301202033_create_cats.rb b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220301202033_create_cats.rb
new file mode 100644
index 0000000..d89b77d
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220301202033_create_cats.rb
@@ -0,0 +1,13 @@
+class CreateCats < ActiveRecord::Migration[7.0]
+  def change
+    create_table :cats do |t|
+      t.date :birth_date, null: false
+      t.string :color, null: false
+      t.string :name, null: false
+      t.string :sex, limit: 1, null: false
+      t.text :description
+
+      t.timestamps
+    end
+  end
+end
diff --git a/rails/homeworks/helpers-layouts-mailer/db/migrate/20220302053135_create_cat_rental_requests.rb b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220302053135_create_cat_rental_requests.rb
new file mode 100644
index 0000000..cbed70b
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220302053135_create_cat_rental_requests.rb
@@ -0,0 +1,12 @@
+class CreateCatRentalRequests < ActiveRecord::Migration[7.0]
+  def change
+    create_table :cat_rental_requests do |t|
+      t.references :cat, null: false, foreign_key: true
+      t.date :start_date, null: false
+      t.date :end_date, null: false
+      t.string :status, null: false, default: 'PENDING'
+
+      t.timestamps
+    end
+  end
+end
diff --git a/rails/homeworks/helpers-layouts-mailer/db/migrate/20220610145144_create_users.rb b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220610145144_create_users.rb
new file mode 100644
index 0000000..b1da12c
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220610145144_create_users.rb
@@ -0,0 +1,13 @@
+class CreateUsers < ActiveRecord::Migration[7.0]
+  def change
+    create_table :users do |t|
+      t.string :username, null: false
+      t.string :password_digest, null: false
+      t.string :session_token, null: false
+
+      t.timestamps
+    end
+    add_index :users, :username, unique: true
+    add_index :users, :session_token, unique: true
+  end
+end
diff --git a/rails/homeworks/helpers-layouts-mailer/db/migrate/20220610214850_add_owner_to_cats.rb b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220610214850_add_owner_to_cats.rb
new file mode 100644
index 0000000..0e0991b
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220610214850_add_owner_to_cats.rb
@@ -0,0 +1,5 @@
+class AddOwnerToCats < ActiveRecord::Migration[7.0]
+  def change
+    add_reference :cats, :owner, null: false, foreign_key: { to_table: :users }
+  end
+end
diff --git a/rails/homeworks/helpers-layouts-mailer/db/migrate/20220618214048_add_requester_to_cat_rental_requests.rb b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220618214048_add_requester_to_cat_rental_requests.rb
new file mode 100644
index 0000000..88033ff
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/db/migrate/20220618214048_add_requester_to_cat_rental_requests.rb
@@ -0,0 +1,5 @@
+class AddRequesterToCatRentalRequests < ActiveRecord::Migration[7.0]
+  def change
+    add_reference :cat_rental_requests, :requester, null: false, foreign_key: { to_table: :users }
+  end
+end
diff --git a/rails/homeworks/helpers-layouts-mailer/db/schema.rb b/rails/homeworks/helpers-layouts-mailer/db/schema.rb
new file mode 100644
index 0000000..d6840a6
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/db/schema.rb
@@ -0,0 +1,54 @@
+# This file is auto-generated from the current state of the database. Instead
+# of editing this file, please use the migrations feature of Active Record to
+# incrementally modify your database, and then regenerate this schema definition.
+#
+# This file is the source Rails uses to define your schema when running `bin/rails
+# db:schema:load`. When creating a new database, `bin/rails db:schema:load` tends to
+# be faster and is potentially less error prone than running all of your
+# migrations from scratch. Old migrations may fail to apply correctly if those
+# migrations use external dependencies or application code.
+#
+# It's strongly recommended that you check this file into your version control system.
+
+ActiveRecord::Schema[7.0].define(version: 2022_06_18_214048) do
+  # These are extensions that must be enabled in order to support this database
+  enable_extension "plpgsql"
+
+  create_table "cat_rental_requests", force: :cascade do |t|
+    t.bigint "cat_id", null: false
+    t.date "start_date", null: false
+    t.date "end_date", null: false
+    t.string "status", default: "PENDING", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.bigint "requester_id", null: false
+    t.index ["cat_id"], name: "index_cat_rental_requests_on_cat_id"
+    t.index ["requester_id"], name: "index_cat_rental_requests_on_requester_id"
+  end
+
+  create_table "cats", force: :cascade do |t|
+    t.date "birth_date", null: false
+    t.string "color", null: false
+    t.string "name", null: false
+    t.string "sex", limit: 1, null: false
+    t.text "description"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.bigint "owner_id", null: false
+    t.index ["owner_id"], name: "index_cats_on_owner_id"
+  end
+
+  create_table "users", force: :cascade do |t|
+    t.string "username", null: false
+    t.string "password_digest", null: false
+    t.string "session_token", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["session_token"], name: "index_users_on_session_token", unique: true
+    t.index ["username"], name: "index_users_on_username", unique: true
+  end
+
+  add_foreign_key "cat_rental_requests", "cats"
+  add_foreign_key "cat_rental_requests", "users", column: "requester_id"
+  add_foreign_key "cats", "users", column: "owner_id"
+end
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/db/seeds.rb b/rails/homeworks/helpers-layouts-mailer/db/seeds.rb
new file mode 100644
index 0000000..555c37c
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/db/seeds.rb
@@ -0,0 +1,7 @@
+# This file should contain all the record creation needed to seed the database with its default values.
+# The data can then be loaded with the bin/rails db:seed command (or created alongside the database with db:setup).
+#
+# Examples:
+#
+#   movies = Movie.create([{ name: "Star Wars" }, { name: "Lord of the Rings" }])
+#   Character.create(name: "Luke", movie: movies.first)
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/lib/assets/.keep b/rails/homeworks/helpers-layouts-mailer/lib/assets/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/lib/tasks/.keep b/rails/homeworks/helpers-layouts-mailer/lib/tasks/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/log/.keep b/rails/homeworks/helpers-layouts-mailer/log/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/public/404.html b/rails/homeworks/helpers-layouts-mailer/public/404.html
new file mode 100644
index 0000000..cb93ac7
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/public/404.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The page you were looking for doesn't exist (404)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/404.html -->
+  <div class="dialog">
+    <div>
+      <h1>The page you were looking for doesn't exist.</h1>
+      <p>You may have mistyped the address or the page may have moved.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/public/422.html b/rails/homeworks/helpers-layouts-mailer/public/422.html
new file mode 100644
index 0000000..aa1a374
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/public/422.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The change you wanted was rejected (422)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/422.html -->
+  <div class="dialog">
+    <div>
+      <h1>The change you wanted was rejected.</h1>
+      <p>Maybe you tried to change something you didn't have access to.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/public/500.html b/rails/homeworks/helpers-layouts-mailer/public/500.html
new file mode 100644
index 0000000..0fd6fca
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/public/500.html
@@ -0,0 +1,66 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>We're sorry, but something went wrong (500)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/500.html -->
+  <div class="dialog">
+    <div>
+      <h1>We're sorry, but something went wrong.</h1>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/public/apple-touch-icon-precomposed.png b/rails/homeworks/helpers-layouts-mailer/public/apple-touch-icon-precomposed.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/public/apple-touch-icon.png b/rails/homeworks/helpers-layouts-mailer/public/apple-touch-icon.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/public/favicon.ico b/rails/homeworks/helpers-layouts-mailer/public/favicon.ico
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/public/robots.txt b/rails/homeworks/helpers-layouts-mailer/public/robots.txt
new file mode 100644
index 0000000..0285b2d
--- /dev/null
+++ b/rails/homeworks/helpers-layouts-mailer/public/robots.txt
@@ -0,0 +1 @@
+# See https://www.robotstxt.org/robotstxt.html for documentation on how to use the robots.txt file
\ No newline at end of file
diff --git a/rails/homeworks/helpers-layouts-mailer/tmp/.keep b/rails/homeworks/helpers-layouts-mailer/tmp/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/tmp/pids/.keep b/rails/homeworks/helpers-layouts-mailer/tmp/pids/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/helpers-layouts-mailer/vendor/.keep b/rails/homeworks/helpers-layouts-mailer/vendor/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/polymorphism-concerns/.gitattributes b/rails/homeworks/polymorphism-concerns/.gitattributes
new file mode 100644
index 0000000..34fb547
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/.gitattributes
@@ -0,0 +1,7 @@
+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/.gitignore b/rails/homeworks/polymorphism-concerns/.gitignore
new file mode 100644
index 0000000..4f0da6f
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/.gitignore
@@ -0,0 +1,26 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/.ruby-version b/rails/homeworks/polymorphism-concerns/.ruby-version
new file mode 100644
index 0000000..94ff29c
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/.ruby-version
@@ -0,0 +1 @@
+3.1.1
diff --git a/rails/homeworks/polymorphism-concerns/Gemfile b/rails/homeworks/polymorphism-concerns/Gemfile
new file mode 100644
index 0000000..32a9841
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/Gemfile
@@ -0,0 +1,33 @@
+source "https://rubygems.org"
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+ruby "3.1.1"
+
+# Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
+gem "rails", "~> 7.0.3"
+
+# The original asset pipeline for Rails [https://github.com/rails/sprockets-rails]
+gem "sprockets-rails"
+
+# Use postgresql as the database for Active Record
+gem "pg", "~> 1.1"
+
+# Use the Puma web server [https://github.com/puma/puma]
+gem "puma", "~> 5.0"
+
+# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
+gem "tzinfo-data", platforms: %i[ mingw mswin x64_mingw jruby ]
+
+group :development, :test do
+  # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
+  gem "byebug", platforms: %i[ mri mingw x64_mingw ]
+end
+
+group :development do
+  # Speed up commands on slow machines / big apps [https://github.com/rails/spring]
+  # gem "spring"
+  gem "annotate"
+  gem "pry-rails"
+  gem "better_errors"
+  gem "binding_of_caller"
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/Gemfile.lock b/rails/homeworks/polymorphism-concerns/Gemfile.lock
new file mode 100644
index 0000000..4b94306
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/Gemfile.lock
@@ -0,0 +1,191 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailbox (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (>= 2.7.1)
+      net-imap
+      net-pop
+      net-smtp
+    actionmailer (7.0.3)
+      actionpack (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (~> 2.5, >= 2.5.4)
+      net-imap
+      net-pop
+      net-smtp
+      rails-dom-testing (~> 2.0)
+    actionpack (7.0.3)
+      actionview (= 7.0.3)
+      activesupport (= 7.0.3)
+      rack (~> 2.0, >= 2.2.0)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (7.0.3)
+      actionpack (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.6.0)
+      nokogiri (>= 1.8.5)
+    actionview (7.0.3)
+      activesupport (= 7.0.3)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.3.6)
+    activemodel (7.0.3)
+      activesupport (= 7.0.3)
+    activerecord (7.0.3)
+      activemodel (= 7.0.3)
+      activesupport (= 7.0.3)
+    activestorage (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activesupport (= 7.0.3)
+      marcel (~> 1.0)
+      mini_mime (>= 1.1.0)
+    activesupport (7.0.3)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+    annotate (3.2.0)
+      activerecord (>= 3.2, < 8.0)
+      rake (>= 10.4, < 14.0)
+    better_errors (2.9.1)
+      coderay (>= 1.0.0)
+      erubi (>= 1.0.0)
+      rack (>= 0.9.0)
+    binding_of_caller (1.0.0)
+      debug_inspector (>= 0.0.1)
+    builder (3.2.4)
+    byebug (11.1.3)
+    coderay (1.1.3)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    debug_inspector (1.1.0)
+    digest (3.1.0)
+    erubi (1.10.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
+      concurrent-ruby (~> 1.0)
+    loofah (2.18.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (1.0.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    minitest (5.15.0)
+    net-imap (0.2.3)
+      digest
+      net-protocol
+      strscan
+    net-pop (0.1.1)
+      digest
+      net-protocol
+      timeout
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    pg (1.3.5)
+    pry (0.14.1)
+      coderay (~> 1.1)
+      method_source (~> 1.0)
+    pry-rails (0.3.9)
+      pry (>= 0.10.4)
+    puma (5.6.4)
+      nio4r (~> 2.0)
+    racc (1.6.0)
+    rack (2.2.3)
+    rack-test (1.1.0)
+      rack (>= 1.0, < 3)
+    rails (7.0.3)
+      actioncable (= 7.0.3)
+      actionmailbox (= 7.0.3)
+      actionmailer (= 7.0.3)
+      actionpack (= 7.0.3)
+      actiontext (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activemodel (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      bundler (>= 1.15.0)
+      railties (= 7.0.3)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.4.2)
+      loofah (~> 2.3)
+    railties (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      method_source
+      rake (>= 12.2)
+      thor (~> 1.0)
+      zeitwerk (~> 2.5)
+    rake (13.0.6)
+    sprockets (4.0.3)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.4.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      sprockets (>= 3.0.0)
+    strscan (3.0.3)
+    thor (1.2.1)
+    timeout (0.2.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    websocket-driver (0.7.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
+    zeitwerk (2.5.4)
+
+PLATFORMS
+  x86_64-darwin-20
+
+DEPENDENCIES
+  annotate
+  better_errors
+  binding_of_caller
+  byebug
+  pg (~> 1.1)
+  pry-rails
+  puma (~> 5.0)
+  rails (~> 7.0.3)
+  sprockets-rails
+  tzinfo-data
+
+RUBY VERSION
+   ruby 3.1.1p18
+
+BUNDLED WITH
+   2.3.8
diff --git a/rails/homeworks/polymorphism-concerns/README.md b/rails/homeworks/polymorphism-concerns/README.md
new file mode 100644
index 0000000..4c65a21
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/README.md
@@ -0,0 +1,126 @@
+# Polymorphism and Concerns
+
+Today you'll make an app that gives toys to cute animals. You'll start with
+corgis and cats. The skeleton--available from the `Download Project` button
+below--already has `Corgi` and `Cat` models. Here's the schema:
+
+**Corgis**
+
+|  column name |  data type  |  details                |
+| :----------- | :---------- | :---------------------- |
+|  id          |  integer    |  not null, primary key  |
+|  name        |  string     |  not null               |
+
+**Cats**
+
+|  column name |  data type  |  details               |
+| :----------- | :---------- | :--------------------- |
+|  id          |  integer    |  not null, primary key |
+|  name        |  string     |  not null              |
+
+## Phase 1: Create a `toys` table
+
+First create a migration that implements the following schema:
+
+**Toys**
+
+|  column name  |  data type  |  details               |
+| :------------ | :---------- | :--------------------- |
+|  id           |  integer    | not null, primary key  |
+|  name         |  string     | not null, indexed, unique with respect to \[toyable_type, toyable_id] |
+|  toyable_type |  string     | not null, indexed with toyable_id |
+|  toyable_id   |  bigint     | not null |
+
+Use the `references` column type with a `polymorphic: true` modifier to generate
+the last two columns:
+
+```ruby
+t.references :toyable, polymorphic: true, null: false
+```
+
+(You can generate the line above from the command line with
+`toyable:references{polymorphic}`.)
+
+> Note: Since a polymorphic `_id` column can refer to more than one table, it
+> cannot have a foreign key constraint.
+
+To ensure that all toys are unique by their `name`, `toyable_id`, and
+`toyable_type` properties, add the following composite index to the migration:
+
+```ruby
+add_index :toys, [:name, :toyable_id, :toyable_type], unique: true
+```
+
+This will assure that each cute animal can have a (single) toy named, e.g.,
+"ball", but no cute animal can have more than one toy with the same name.
+
+When you have finished setting up your migration, run `rails db:migrate`.
+
+## Phase 2: Create polymorphic associations
+
+The purpose of a polymorphic association is to allow one model to belong to
+multiple models on a single association. Using as little code as possible, you
+want to give a `toys` association to `Corgi`s, `Cat`s, and whatever other cute
+animals you choose.
+
+First, create a `Toy` model and build a polymorphic `belongs_to` association on
+`toyable`. (If you used the model generator, this will already have been done
+for you.) You should also validate a `Toy`'s `uniqueness` constraint on `:name`
+and `:toyable` (`toyable_type` and `toyable_id` in the database). Refer to the
+Rails guides for help with [polymorphic syntax] and [scoped `uniqueness`
+checks].
+
+Next, build corresponding `has_many` associations in the `Corgi` and `Cat`
+models. These should both be named `toys`.
+
+Add some `Toy`s to the seed file and run `rails db:seed`. Check that your
+associations work as expected.
+
+[polymorphic syntax]: http://guides.rubyonrails.org/association_basics.html#polymorphic-associations
+[scoped `uniqueness` checks]: http://guides.rubyonrails.org/active_record_validations.html#uniqueness
+
+## Phase 2: Create a Toyable Concern
+
+What if you want to give more toys to more cute animals? You'd want each new
+class to have a `#receive_toy(name)` method and a `toys` association. Sounds
+like a perfect opportunity to use a concern!
+
+A concern (see the reading for more details) is just a [module][module] that
+extends `ActiveSupport::Concern`. Like other modules, a concern permits shared
+functionality across classes.
+
+Create a file called __toyable.rb__ in the __app/models/concerns__ directory.
+Paste the following into your file:
+
+```ruby
+module Toyable
+  extend ActiveSupport::Concern
+
+  included do
+
+  end
+
+  def receive_toy(name)
+
+  end
+end
+```
+
+Write the code for the `toys` association within the `included` block. Whenever
+the module is included in a class, all code inside this block is executed
+within the context of the class that includes it.
+
+Next write a `#receive_toy(name)` method. Any animal instance whose class
+includes the `Toyable` concern can call this method. This method should first
+find or create a toy whose name matches the argument. Next it should add this
+toy to `self`'s `toys`. For both steps, you may wish to use the Active Record
+`#find_or_create_by` [method].
+
+After you've created your `Toyable` concern, go back to your `Corgi` and `Cat`
+models and `include` your new `Toyable` concern. You can delete the associations
+you wrote previously.
+
+Test your code and call it a night!
+
+[module]: https://ruby-doc.com/docs/ProgrammingRuby/html/tut_modules.html
+[method]: https://api.rubyonrails.org/classes/ActiveRecord/Relation.html#method-i-find_or_create_by
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/Rakefile b/rails/homeworks/polymorphism-concerns/Rakefile
new file mode 100644
index 0000000..d298243
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/Rakefile
@@ -0,0 +1,6 @@
+# Add your own tasks in files placed in lib/tasks ending in .rake,
+# for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
+
+require_relative "config/application"
+
+Rails.application.load_tasks
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/app/assets/config/manifest.js b/rails/homeworks/polymorphism-concerns/app/assets/config/manifest.js
new file mode 100644
index 0000000..f83f92b
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/app/assets/config/manifest.js
@@ -0,0 +1,2 @@
+//= link_tree ../images
+//= link_directory ../stylesheets .css
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/app/assets/images/.keep b/rails/homeworks/polymorphism-concerns/app/assets/images/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/polymorphism-concerns/app/assets/stylesheets/application.css b/rails/homeworks/polymorphism-concerns/app/assets/stylesheets/application.css
new file mode 100644
index 0000000..21c9ac5
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/app/assets/stylesheets/application.css
@@ -0,0 +1,15 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS (and SCSS, if configured) file within this directory, lib/assets/stylesheets, or any plugin's
+ * vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree .
+ *= require_self
+ */
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/app/controllers/application_controller.rb b/rails/homeworks/polymorphism-concerns/app/controllers/application_controller.rb
new file mode 100644
index 0000000..09705d1
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/app/controllers/application_controller.rb
@@ -0,0 +1,2 @@
+class ApplicationController < ActionController::Base
+end
diff --git a/rails/homeworks/polymorphism-concerns/app/controllers/concerns/.keep b/rails/homeworks/polymorphism-concerns/app/controllers/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/polymorphism-concerns/app/helpers/application_helper.rb b/rails/homeworks/polymorphism-concerns/app/helpers/application_helper.rb
new file mode 100644
index 0000000..de6be79
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/app/helpers/application_helper.rb
@@ -0,0 +1,2 @@
+module ApplicationHelper
+end
diff --git a/rails/homeworks/polymorphism-concerns/app/models/application_record.rb b/rails/homeworks/polymorphism-concerns/app/models/application_record.rb
new file mode 100644
index 0000000..b63caeb
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/app/models/application_record.rb
@@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+  primary_abstract_class
+end
diff --git a/rails/homeworks/polymorphism-concerns/app/models/cat.rb b/rails/homeworks/polymorphism-concerns/app/models/cat.rb
new file mode 100644
index 0000000..8a1f427
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/app/models/cat.rb
@@ -0,0 +1,12 @@
+# == Schema Information
+#
+# Table name: cats
+#
+#  id         :bigint           not null, primary key
+#  name       :string           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+class Cat < ApplicationRecord
+  validates :name, presence: true   
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/app/models/concerns/.keep b/rails/homeworks/polymorphism-concerns/app/models/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/polymorphism-concerns/app/models/corgi.rb b/rails/homeworks/polymorphism-concerns/app/models/corgi.rb
new file mode 100644
index 0000000..958e0aa
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/app/models/corgi.rb
@@ -0,0 +1,12 @@
+# == Schema Information
+#
+# Table name: corgis
+#
+#  id         :bigint           not null, primary key
+#  name       :string           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+class Corgi < ApplicationRecord
+  validates :name, presence: true
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/app/views/layouts/application.html.erb b/rails/homeworks/polymorphism-concerns/app/views/layouts/application.html.erb
new file mode 100644
index 0000000..893b7bb
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/app/views/layouts/application.html.erb
@@ -0,0 +1,15 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>PolymorphismAndConcerns</title>
+    <meta name="viewport" content="width=device-width,initial-scale=1">
+    <%= csrf_meta_tags %>
+    <%= csp_meta_tag %>
+
+    <%= stylesheet_link_tag "application" %>
+  </head>
+
+  <body>
+    <%= yield %>
+  </body>
+</html>
diff --git a/rails/homeworks/polymorphism-concerns/bin/bundle b/rails/homeworks/polymorphism-concerns/bin/bundle
new file mode 100644
index 0000000..15f37e3
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/bin/bundle
@@ -0,0 +1,114 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'bundle' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "rubygems"
+
+m = Module.new do
+  module_function
+
+  def invoked_as_script?
+    File.expand_path($0) == File.expand_path(__FILE__)
+  end
+
+  def env_var_version
+    ENV["BUNDLER_VERSION"]
+  end
+
+  def cli_arg_version
+    return unless invoked_as_script? # don't want to hijack other binstubs
+    return unless "update".start_with?(ARGV.first || " ") # must be running `bundle update`
+    bundler_version = nil
+    update_index = nil
+    ARGV.each_with_index do |a, i|
+      if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
+        bundler_version = a
+      end
+      next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
+      bundler_version = $1
+      update_index = i
+    end
+    bundler_version
+  end
+
+  def gemfile
+    gemfile = ENV["BUNDLE_GEMFILE"]
+    return gemfile if gemfile && !gemfile.empty?
+
+    File.expand_path("../../Gemfile", __FILE__)
+  end
+
+  def lockfile
+    lockfile =
+      case File.basename(gemfile)
+      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
+      else "#{gemfile}.lock"
+      end
+    File.expand_path(lockfile)
+  end
+
+  def lockfile_version
+    return unless File.file?(lockfile)
+    lockfile_contents = File.read(lockfile)
+    return unless lockfile_contents =~ /\n\nBUNDLED WITH\n\s{2,}(#{Gem::Version::VERSION_PATTERN})\n/
+    Regexp.last_match(1)
+  end
+
+  def bundler_requirement
+    @bundler_requirement ||=
+      env_var_version || cli_arg_version ||
+        bundler_requirement_for(lockfile_version)
+  end
+
+  def bundler_requirement_for(version)
+    return "#{Gem::Requirement.default}.a" unless version
+
+    bundler_gem_version = Gem::Version.new(version)
+
+    requirement = bundler_gem_version.approximate_recommendation
+
+    return requirement unless Gem.rubygems_version < Gem::Version.new("2.7.0")
+
+    requirement += ".a" if bundler_gem_version.prerelease?
+
+    requirement
+  end
+
+  def load_bundler!
+    ENV["BUNDLE_GEMFILE"] ||= gemfile
+
+    activate_bundler
+  end
+
+  def activate_bundler
+    gem_error = activation_error_handling do
+      gem "bundler", bundler_requirement
+    end
+    return if gem_error.nil?
+    require_error = activation_error_handling do
+      require "bundler/version"
+    end
+    return if require_error.nil? && Gem::Requirement.new(bundler_requirement).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+    warn "Activating bundler (#{bundler_requirement}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_requirement}'`"
+    exit 42
+  end
+
+  def activation_error_handling
+    yield
+    nil
+  rescue StandardError, LoadError => e
+    e
+  end
+end
+
+m.load_bundler!
+
+if m.invoked_as_script?
+  load Gem.bin_path("bundler", "bundle")
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/bin/rails b/rails/homeworks/polymorphism-concerns/bin/rails
new file mode 100644
index 0000000..fa3c01a
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/bin/rails
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+APP_PATH = File.expand_path("../config/application", __dir__)
+require_relative "../config/boot"
+require "rails/commands"
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/bin/rake b/rails/homeworks/polymorphism-concerns/bin/rake
new file mode 100644
index 0000000..19d605d
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/bin/rake
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+require_relative "../config/boot"
+require "rake"
+Rake.application.run
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/bin/setup b/rails/homeworks/polymorphism-concerns/bin/setup
new file mode 100644
index 0000000..9bd670f
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/bin/setup
@@ -0,0 +1,33 @@
+#!/usr/bin/env ruby
+require "fileutils"
+
+# path to your application root.
+APP_ROOT = File.expand_path("..", __dir__)
+
+def system!(*args)
+  system(*args) || abort("\n== Command #{args} failed ==")
+end
+
+FileUtils.chdir APP_ROOT do
+  # This script is a way to set up or update your development environment automatically.
+  # This script is idempotent, so that you can run it at any time and get an expectable outcome.
+  # Add necessary setup steps to this file.
+
+  puts "== Installing dependencies =="
+  system! "gem install bundler --conservative"
+  system("bundle check") || system!("bundle install")
+
+  # puts "\n== Copying sample files =="
+  # unless File.exist?("config/database.yml")
+  #   FileUtils.cp "config/database.yml.sample", "config/database.yml"
+  # end
+
+  puts "\n== Preparing database =="
+  system! "bin/rails db:prepare"
+
+  puts "\n== Removing old logs and tempfiles =="
+  system! "bin/rails log:clear tmp:clear"
+
+  puts "\n== Restarting application server =="
+  system! "bin/rails restart"
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config.ru b/rails/homeworks/polymorphism-concerns/config.ru
new file mode 100644
index 0000000..38cc27a
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config.ru
@@ -0,0 +1,6 @@
+# This file is used by Rack-based servers to start the application.
+
+require_relative "config/environment"
+
+run Rails.application
+Rails.application.load_server
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/application.rb b/rails/homeworks/polymorphism-concerns/config/application.rb
new file mode 100644
index 0000000..7d726f9
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/application.rb
@@ -0,0 +1,37 @@
+require_relative "boot"
+
+require "rails"
+# Pick the frameworks you want:
+require "active_model/railtie"
+# require "active_job/railtie"
+require "active_record/railtie"
+# require "active_storage/engine"
+require "action_controller/railtie"
+# require "action_mailer/railtie"
+# require "action_mailbox/engine"
+# require "action_text/engine"
+require "action_view/railtie"
+# require "action_cable/engine"
+# require "rails/test_unit/railtie"
+
+# Require the gems listed in Gemfile, including any gems
+# you've limited to :test, :development, or :production.
+Bundler.require(*Rails.groups)
+
+module PolymorphismAndConcerns
+  class Application < Rails::Application
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults 7.0
+
+    # Configuration for the application, engines, and railties goes here.
+    #
+    # These settings can be overridden in specific environments using the files
+    # in config/environments, which are processed later.
+    #
+    # config.time_zone = "Central Time (US & Canada)"
+    # config.eager_load_paths << Rails.root.join("extras")
+
+    # Don't generate system test files.
+    config.generators.system_tests = nil
+  end
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/boot.rb b/rails/homeworks/polymorphism-concerns/config/boot.rb
new file mode 100644
index 0000000..2820116
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/boot.rb
@@ -0,0 +1,3 @@
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+
+require "bundler/setup" # Set up gems listed in the Gemfile.
diff --git a/rails/homeworks/polymorphism-concerns/config/credentials.yml.enc b/rails/homeworks/polymorphism-concerns/config/credentials.yml.enc
new file mode 100644
index 0000000..a9f52f7
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/credentials.yml.enc
@@ -0,0 +1 @@
+l+dFA1LRss3yKaPmps/IuWyls5V7pFCdeQAtzd+4cTuyXSmAO/vYst/lZorLL/plkyLEeWWz9kTwUpVPBusFJ+PeqK03IbWpdKqricIzRPkxklZ6g3OPVbZaWAUVFc/h0J+qO3fameyXsC5Rni8cD40fyFZG0J/SCEJ8Lv9EBrfffBQ5Kos5pyCiz/Cu2bRvTuPiCGgpk9xBwg/O8F9QyS9KZfkkPl5n0GkoY+yN8fsYzugcYfYkeQUZKiLb+iwBAVqP06jnOuUd85lXobwjE4Mdi7qOot5YvHI/Z1iPCBRC+yIojZwQUe/7ReO6zDleEqLsyUzvWtDoJYqwO8/7iCkBqCTXZfzFN+lDLlVSwlc1XSstXQhhNRI35X2JhZGXP8xmb9rTKssPKg5SOsVIvSdXoHgaavdEJ8em--SCWrdbLNF8bLLeIj--jIJegijRITENizUlINRg2A==
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/database.yml b/rails/homeworks/polymorphism-concerns/config/database.yml
new file mode 100644
index 0000000..bc8895e
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/database.yml
@@ -0,0 +1,86 @@
+# PostgreSQL. Versions 9.3 and up are supported.
+#
+# Install the pg driver:
+#   gem install pg
+# On macOS with Homebrew:
+#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
+# On macOS with MacPorts:
+#   gem install pg -- --with-pg-config=/opt/local/lib/postgresql84/bin/pg_config
+# On Windows:
+#   gem install pg
+#       Choose the win32 build.
+#       Install PostgreSQL and put its /bin directory on your path.
+#
+# Configure Using Gemfile
+# gem "pg"
+#
+default: &default
+  adapter: postgresql
+  encoding: unicode
+  # For details on connection pooling, see Rails configuration guide
+  # https://guides.rubyonrails.org/configuring.html#database-pooling
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+
+development:
+  <<: *default
+  database: polymorphism_and_concerns_development
+
+  # The specified database role being used to connect to postgres.
+  # To create additional roles in postgres see `$ createuser --help`.
+  # When left blank, postgres will use the default role. This is
+  # the same name as the operating system user running Rails.
+  #username: polymorphism_and_concerns
+
+  # The password associated with the postgres role (username).
+  #password:
+
+  # Connect on a TCP socket. Omitted by default since the client uses a
+  # domain socket that doesn't need configuration. Windows does not have
+  # domain sockets, so uncomment these lines.
+  #host: localhost
+
+  # The TCP port the server listens on. Defaults to 5432.
+  # If your server runs on a different port number, change accordingly.
+  #port: 5432
+
+  # Schema search path. The server defaults to $user,public
+  #schema_search_path: myapp,sharedapp,public
+
+  # Minimum log levels, in increasing order:
+  #   debug5, debug4, debug3, debug2, debug1,
+  #   log, notice, warning, error, fatal, and panic
+  # Defaults to warning.
+  #min_messages: notice
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: polymorphism_and_concerns_test
+
+# As with config/credentials.yml, you never want to store sensitive information,
+# like your database password, in your source code. If your source code is
+# ever seen by anyone, they now have access to your database.
+#
+# Instead, provide the password or a full connection URL as an environment
+# variable when you boot the app. For example:
+#
+#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
+#
+# If the connection URL is provided in the special DATABASE_URL environment
+# variable, Rails will automatically merge its configuration values on top of
+# the values provided in this file. Alternatively, you can specify a connection
+# URL environment variable explicitly:
+#
+#   production:
+#     url: <%= ENV["MY_APP_DATABASE_URL"] %>
+#
+# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
+# for a full overview on how database connection configuration can be specified.
+#
+production:
+  <<: *default
+  database: polymorphism_and_concerns_production
+  username: polymorphism_and_concerns
+  password: <%= ENV["POLYMORPHISM_AND_CONCERNS_DATABASE_PASSWORD"] %>
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/environment.rb b/rails/homeworks/polymorphism-concerns/config/environment.rb
new file mode 100644
index 0000000..445c788
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/environment.rb
@@ -0,0 +1,5 @@
+# Load the Rails application.
+require_relative "application"
+
+# Initialize the Rails application.
+Rails.application.initialize!
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/environments/development.rb b/rails/homeworks/polymorphism-concerns/config/environments/development.rb
new file mode 100644
index 0000000..851adc5
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/environments/development.rb
@@ -0,0 +1,62 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # In the development environment your application's code is reloaded any time
+  # it changes. This slows down response time but is perfect for development
+  # since you don't have to restart the web server when you make code changes.
+  config.cache_classes = false
+
+  # Do not eager load code on boot.
+  config.eager_load = false
+
+  # Show full error reports.
+  config.consider_all_requests_local = true
+
+  # Enable server timing
+  config.server_timing = true
+
+  # Enable/disable caching. By default caching is disabled.
+  # Run rails dev:cache to toggle caching.
+  if Rails.root.join("tmp/caching-dev.txt").exist?
+    config.action_controller.perform_caching = true
+    config.action_controller.enable_fragment_cache_logging = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      "Cache-Control" => "public, max-age=#{2.days.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
+
+  # Print deprecation notices to the Rails logger.
+  config.active_support.deprecation = :log
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raise an error on page load if there are pending migrations.
+  config.active_record.migration_error = :page_load
+
+  # Highlight code that triggered database queries in logs.
+  config.active_record.verbose_query_logs = true
+
+  # Suppress logger output for asset requests.
+  config.assets.quiet = true
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+
+  # Uncomment if you wish to allow Action Cable access from any origin.
+  # config.action_cable.disable_request_forgery_protection = true
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/environments/production.rb b/rails/homeworks/polymorphism-concerns/config/environments/production.rb
new file mode 100644
index 0000000..6aee001
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/environments/production.rb
@@ -0,0 +1,75 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Code is not reloaded between requests.
+  config.cache_classes = true
+
+  # Eager load code on boot. This eager loads most of Rails and
+  # your application in memory, allowing both threaded web servers
+  # and those relying on copy on write to perform better.
+  # Rake tasks automatically ignore this option for performance.
+  config.eager_load = true
+
+  # Full error reports are disabled and caching is turned on.
+  config.consider_all_requests_local       = false
+  config.action_controller.perform_caching = true
+
+  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  # config.require_master_key = true
+
+  # Disable serving static files from the `/public` folder by default since
+  # Apache or NGINX already handles this.
+  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
+
+  # Compress CSS using a preprocessor.
+  # config.assets.css_compressor = :sass
+
+  # Do not fallback to assets pipeline if a precompiled asset is missed.
+  config.assets.compile = false
+
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.asset_host = "http://assets.example.com"
+
+  # Specifies the header that your server uses for sending files.
+  # config.action_dispatch.x_sendfile_header = "X-Sendfile" # for Apache
+  # config.action_dispatch.x_sendfile_header = "X-Accel-Redirect" # for NGINX
+
+  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
+  # config.force_ssl = true
+
+  # Include generic and useful information about system operation, but avoid logging too much
+  # information to avoid inadvertent exposure of personally identifiable information (PII).
+  config.log_level = :info
+
+  # Prepend all log lines with the following tags.
+  config.log_tags = [ :request_id ]
+
+  # Use a different cache store in production.
+  # config.cache_store = :mem_cache_store
+
+  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
+  # the I18n.default_locale when a translation cannot be found).
+  config.i18n.fallbacks = true
+
+  # Don't log any deprecations.
+  config.active_support.report_deprecations = false
+
+  # Use default logging formatter so that PID and timestamp are not suppressed.
+  config.log_formatter = ::Logger::Formatter.new
+
+  # Use a different logger for distributed setups.
+  # require "syslog/logger"
+  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
+
+  if ENV["RAILS_LOG_TO_STDOUT"].present?
+    logger           = ActiveSupport::Logger.new(STDOUT)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/environments/test.rb b/rails/homeworks/polymorphism-concerns/config/environments/test.rb
new file mode 100644
index 0000000..da62dfc
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/environments/test.rb
@@ -0,0 +1,50 @@
+require "active_support/core_ext/integer/time"
+
+# The test environment is used exclusively to run your application's
+# test suite. You never need to work with it otherwise. Remember that
+# your test database is "scratch space" for the test suite and is wiped
+# and recreated between test runs. Don't rely on the data there!
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Turn false under Spring and add config.action_view.cache_template_loading = true.
+  config.cache_classes = true
+
+  # Eager loading loads your whole application. When running a single test locally,
+  # this probably isn't necessary. It's a good idea to do in a continuous integration
+  # system, or in some way before deploying your code.
+  config.eager_load = ENV["CI"].present?
+
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = {
+    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
+  }
+
+  # Show full error reports and disable caching.
+  config.consider_all_requests_local       = true
+  config.action_controller.perform_caching = false
+  config.cache_store = :null_store
+
+  # Raise exceptions instead of rendering exception templates.
+  config.action_dispatch.show_exceptions = false
+
+  # Disable request forgery protection in test environment.
+  config.action_controller.allow_forgery_protection = false
+
+  # Print deprecation notices to the stderr.
+  config.active_support.deprecation = :stderr
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/initializers/assets.rb b/rails/homeworks/polymorphism-concerns/config/initializers/assets.rb
new file mode 100644
index 0000000..bd8332f
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/initializers/assets.rb
@@ -0,0 +1,12 @@
+# Be sure to restart your server when you modify this file.
+
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = "1.0"
+
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/initializers/content_security_policy.rb b/rails/homeworks/polymorphism-concerns/config/initializers/content_security_policy.rb
new file mode 100644
index 0000000..b713b2f
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/initializers/content_security_policy.rb
@@ -0,0 +1,25 @@
+# Be sure to restart your server when you modify this file.
+
+# Define an application-wide content security policy.
+# See the Securing Rails Applications Guide for more information:
+# https://guides.rubyonrails.org/security.html#content-security-policy-header
+
+# Rails.application.configure do
+#   config.content_security_policy do |policy|
+#     policy.default_src :self, :https
+#     policy.font_src    :self, :https, :data
+#     policy.img_src     :self, :https, :data
+#     policy.object_src  :none
+#     policy.script_src  :self, :https
+#     policy.style_src   :self, :https
+#     # Specify URI for violation reports
+#     # policy.report_uri "/csp-violation-report-endpoint"
+#   end
+#
+#   # Generate session nonces for permitted importmap and inline scripts
+#   config.content_security_policy_nonce_generator = ->(request) { request.session.id.to_s }
+#   config.content_security_policy_nonce_directives = %w(script-src)
+#
+#   # Report violations without enforcing the policy.
+#   # config.content_security_policy_report_only = true
+# end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/initializers/filter_parameter_logging.rb b/rails/homeworks/polymorphism-concerns/config/initializers/filter_parameter_logging.rb
new file mode 100644
index 0000000..b4db5f6
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/initializers/filter_parameter_logging.rb
@@ -0,0 +1,8 @@
+# Be sure to restart your server when you modify this file.
+
+# Configure parameters to be filtered from the log file. Use this to limit dissemination of
+# sensitive information. See the ActiveSupport::ParameterFilter documentation for supported
+# notations and behaviors.
+Rails.application.config.filter_parameters += [
+  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
+]
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/initializers/inflections.rb b/rails/homeworks/polymorphism-concerns/config/initializers/inflections.rb
new file mode 100644
index 0000000..df431d7
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/initializers/inflections.rb
@@ -0,0 +1,16 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new inflection rules using the following format. Inflections
+# are locale specific, and you may define rules for as many different
+# locales as you wish. All of these examples are active by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.plural /^(ox)$/i, "\\1en"
+#   inflect.singular /^(ox)en/i, "\\1"
+#   inflect.irregular "person", "people"
+#   inflect.uncountable %w( fish sheep )
+# end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym "RESTful"
+# end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/initializers/permissions_policy.rb b/rails/homeworks/polymorphism-concerns/config/initializers/permissions_policy.rb
new file mode 100644
index 0000000..dd30019
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/initializers/permissions_policy.rb
@@ -0,0 +1,11 @@
+# Define an application-wide HTTP permissions policy. For further
+# information see https://developers.google.com/web/updates/2018/06/feature-policy
+#
+# Rails.application.config.permissions_policy do |f|
+#   f.camera      :none
+#   f.gyroscope   :none
+#   f.microphone  :none
+#   f.usb         :none
+#   f.fullscreen  :self
+#   f.payment     :self, "https://secure.example.com"
+# end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/locales/en.yml b/rails/homeworks/polymorphism-concerns/config/locales/en.yml
new file mode 100644
index 0000000..30c9973
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/locales/en.yml
@@ -0,0 +1,33 @@
+# Files in the config/locales directory are used for internationalization
+# and are automatically loaded by Rails. If you want to use locales other
+# than English, add the necessary files in this directory.
+#
+# To use the locales, use `I18n.t`:
+#
+#     I18n.t "hello"
+#
+# In views, this is aliased to just `t`:
+#
+#     <%= t("hello") %>
+#
+# To use a different locale, set it with `I18n.locale`:
+#
+#     I18n.locale = :es
+#
+# This would use the information in config/locales/es.yml.
+#
+# The following keys must be escaped otherwise they will not be retrieved by
+# the default I18n backend:
+#
+# true, false, on, off, yes, no
+#
+# Instead, surround them with single quotes.
+#
+# en:
+#   "true": "foo"
+#
+# To learn more, please read the Rails Internationalization guide
+# available at https://guides.rubyonrails.org/i18n.html.
+
+en:
+  hello: "Hello world"
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/puma.rb b/rails/homeworks/polymorphism-concerns/config/puma.rb
new file mode 100644
index 0000000..411b18d
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/puma.rb
@@ -0,0 +1,43 @@
+# Puma can serve each request in a thread from an internal thread pool.
+# The `threads` method setting takes two numbers: a minimum and maximum.
+# Any libraries that use thread pools should be configured to match
+# the maximum value specified for Puma. Default is set to 5 threads for minimum
+# and maximum; this matches the default thread size of Active Record.
+#
+max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
+min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count }
+threads min_threads_count, max_threads_count
+
+# Specifies the `worker_timeout` threshold that Puma will use to wait before
+# terminating a worker in development environments.
+#
+worker_timeout 3600 if ENV.fetch("RAILS_ENV", "development") == "development"
+
+# Specifies the `port` that Puma will listen on to receive requests; default is 3000.
+#
+port ENV.fetch("PORT") { 3000 }
+
+# Specifies the `environment` that Puma will run in.
+#
+environment ENV.fetch("RAILS_ENV") { "development" }
+
+# Specifies the `pidfile` that Puma will use.
+pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
+
+# Specifies the number of `workers` to boot in clustered mode.
+# Workers are forked web server processes. If using threads and workers together
+# the concurrency of the application would be max `threads` * `workers`.
+# Workers do not work on JRuby or Windows (both of which do not support
+# processes).
+#
+# workers ENV.fetch("WEB_CONCURRENCY") { 2 }
+
+# Use the `preload_app!` method when specifying a `workers` number.
+# This directive tells Puma to first boot the application and load code
+# before forking the application. This takes advantage of Copy On Write
+# process behavior so workers use less memory.
+#
+# preload_app!
+
+# Allow puma to be restarted by `bin/rails restart` command.
+plugin :tmp_restart
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/config/routes.rb b/rails/homeworks/polymorphism-concerns/config/routes.rb
new file mode 100644
index 0000000..4510eb1
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/config/routes.rb
@@ -0,0 +1,6 @@
+Rails.application.routes.draw do
+  # Define your application routes per the DSL in https://guides.rubyonrails.org/routing.html
+
+  # Defines the root path route ("/")
+  # root "articles#index"
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/db/migrate/20220525200711_create_cats.rb b/rails/homeworks/polymorphism-concerns/db/migrate/20220525200711_create_cats.rb
new file mode 100644
index 0000000..074b11a
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/db/migrate/20220525200711_create_cats.rb
@@ -0,0 +1,9 @@
+class CreateCats < ActiveRecord::Migration[7.0]
+  def change
+    create_table :cats do |t|
+      t.string :name, null: false
+
+      t.timestamps
+    end
+  end
+end
diff --git a/rails/homeworks/polymorphism-concerns/db/migrate/20220525200732_create_corgis.rb b/rails/homeworks/polymorphism-concerns/db/migrate/20220525200732_create_corgis.rb
new file mode 100644
index 0000000..e447649
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/db/migrate/20220525200732_create_corgis.rb
@@ -0,0 +1,9 @@
+class CreateCorgis < ActiveRecord::Migration[7.0]
+  def change
+    create_table :corgis do |t|
+      t.string :name, null: false
+
+      t.timestamps
+    end
+  end
+end
diff --git a/rails/homeworks/polymorphism-concerns/db/schema.rb b/rails/homeworks/polymorphism-concerns/db/schema.rb
new file mode 100644
index 0000000..c211c3d
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/db/schema.rb
@@ -0,0 +1,29 @@
+# This file is auto-generated from the current state of the database. Instead
+# of editing this file, please use the migrations feature of Active Record to
+# incrementally modify your database, and then regenerate this schema definition.
+#
+# This file is the source Rails uses to define your schema when running `bin/rails
+# db:schema:load`. When creating a new database, `bin/rails db:schema:load` tends to
+# be faster and is potentially less error prone than running all of your
+# migrations from scratch. Old migrations may fail to apply correctly if those
+# migrations use external dependencies or application code.
+#
+# It's strongly recommended that you check this file into your version control system.
+
+ActiveRecord::Schema[7.0].define(version: 2022_05_25_202913) do
+  # These are extensions that must be enabled in order to support this database
+  enable_extension "plpgsql"
+
+  create_table "cats", force: :cascade do |t|
+    t.string "name", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+  end
+
+  create_table "corgis", force: :cascade do |t|
+    t.string "name", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+  end
+
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/db/seeds.rb b/rails/homeworks/polymorphism-concerns/db/seeds.rb
new file mode 100644
index 0000000..398b663
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/db/seeds.rb
@@ -0,0 +1,29 @@
+# This file should contain all the record creation needed to seed the database with its default values.
+# The data can then be loaded with the bin/rails db:seed command (or created alongside the database with db:setup).
+#
+# Examples:
+#
+#   movies = Movie.create([{ name: "Star Wars" }, { name: "Lord of the Rings" }])
+#   Character.create(name: "Luke", movie: movies.first)
+
+ApplicationRecord.transaction do
+  # These `destroy_all` commands are not necessary--but will not hurt--if you
+  # use `rails db:seed:replant`.
+  puts "Destroying tables..."
+  Corgi.destroy_all
+  Cat.destroy_all
+
+  # Reset the id (i.e., primary key) counters for each table to start at 1
+  puts "Resetting primary keys..."
+  %w(cats corgis).each do |table_name|
+    ApplicationRecord.connection.reset_pk_sequence!(table_name)
+  end
+
+  puts "Populating seed data..."
+  cat1 = Cat.create!(name: "Sennacy")
+  cat2 = Cat.create!(name: "Garfield")
+  corgi1 = Corgi.create!(name: "Shelly")
+  corgi2 = Corgi.create!(name: "Prisca")
+
+  puts "Done!"
+end
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/lib/assets/.keep b/rails/homeworks/polymorphism-concerns/lib/assets/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/polymorphism-concerns/lib/tasks/.keep b/rails/homeworks/polymorphism-concerns/lib/tasks/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/polymorphism-concerns/log/.keep b/rails/homeworks/polymorphism-concerns/log/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/homeworks/polymorphism-concerns/public/404.html b/rails/homeworks/polymorphism-concerns/public/404.html
new file mode 100644
index 0000000..cb93ac7
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/public/404.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The page you were looking for doesn't exist (404)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/404.html -->
+  <div class="dialog">
+    <div>
+      <h1>The page you were looking for doesn't exist.</h1>
+      <p>You may have mistyped the address or the page may have moved.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/public/422.html b/rails/homeworks/polymorphism-concerns/public/422.html
new file mode 100644
index 0000000..aa1a374
--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/public/422.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The change you wanted was rejected (422)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/422.html -->
+  <div class="dialog">
+    <div>
+      <h1>The change you wanted was rejected.</h1>
+      <p>Maybe you tried to change something you didn't have access to.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/public/500.html b/rails/homeworks/polymorphism-concerns/public/500.html
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+++ b/rails/homeworks/polymorphism-concerns/public/500.html
@@ -0,0 +1,66 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>We're sorry, but something went wrong (500)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/500.html -->
+  <div class="dialog">
+    <div>
+      <h1>We're sorry, but something went wrong.</h1>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/public/apple-touch-icon-precomposed.png b/rails/homeworks/polymorphism-concerns/public/apple-touch-icon-precomposed.png
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diff --git a/rails/homeworks/polymorphism-concerns/public/favicon.ico b/rails/homeworks/polymorphism-concerns/public/favicon.ico
new file mode 100644
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diff --git a/rails/homeworks/polymorphism-concerns/public/robots.txt b/rails/homeworks/polymorphism-concerns/public/robots.txt
new file mode 100644
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--- /dev/null
+++ b/rails/homeworks/polymorphism-concerns/public/robots.txt
@@ -0,0 +1 @@
+# See https://www.robotstxt.org/robotstxt.html for documentation on how to use the robots.txt file
\ No newline at end of file
diff --git a/rails/homeworks/polymorphism-concerns/tmp/.keep b/rails/homeworks/polymorphism-concerns/tmp/.keep
new file mode 100644
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diff --git a/rails/homeworks/polymorphism-concerns/tmp/pids/.keep b/rails/homeworks/polymorphism-concerns/tmp/pids/.keep
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diff --git a/rails/homeworks/polymorphism-concerns/vendor/.keep b/rails/homeworks/polymorphism-concerns/vendor/.keep
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diff --git a/rails/homeworks/rails-auth/README.md b/rails/homeworks/rails-auth/README.md
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+++ b/rails/homeworks/rails-auth/README.md
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+# Rails Auth Homework
+
+This evening, you will be building a User model for a Rails auth system. This
+project won't end in an app with login/logout functionality, but this is a
+concept that you will use over and over again.
+
+**Refer to the Auth I and Auth II readings if you get stuck.**
+
+## Phase 0: Creating a new rails project
+
+* `rails new <app_name> -G -T --minimal --database=postgresql`
+* `rails db:create`
+* Grab the __.gitattributes__ and __.gitignore__ files from the repo at the
+  `Download Project` button below (or from one of your previous projects).
+* Add `gem "bcrypt"` to the top level of your __Gemfile__. Change `debug` to
+  `byebug` if you wish and add any other gems you want included. Then `bundle
+  install`.
+
+## Phase 1: Create a User model and migration
+
+* Create a `User` model with the following columns and types:
+
+  ```sh
+  username:string password_digest:string session_token:string
+  ```
+
+* Add the appropriate constraints and indexes to the migration.
+* Run `rails db:migrate` and check __schema.rb__ to make sure it worked.
+
+## Phase 2: Add validations to the User model
+
+* Validate the presence of `username` and `session_token`
+* Validate the presence of `password_digest` and set the error message to
+  `Password can't be blank`
+* Validate the length of `password` and set `allow_nil` to `true`
+* Make sure that `ensure_session_token` gets called before validations
+
+## Phase 3: Add helper methods to the User model
+
+* Write `::find_by_credentials`
+  * This method takes in a `username` and a `password` and returns the user that
+    matches (or `nil` if no match)
+  * This method should use `#is_password?` (see below).
+* Write `#generate_unique_session_token`
+  * This method uses `SecureRandom::urlsafe_base64` to return a unique 16-digit
+    pseudorandom string
+* Write `#password=`
+  * This method sets `@password` equal to the argument given so that the
+    appropriate validation can happen
+  * This method also encrypts the argument given and saves it as this user's
+    `password_digest`
+  * Remember: you have to add an `attr_reader` for `password` for the validation
+    to occur!
+* Write `#is_password?`
+  * This method takes a `password` and checks it against the `password_digest`
+    to determine whether or not `password` is, in fact, the user's password.
+* Write `#reset_session_token!`
+  * This method resets the user's `session_token` and saves the user
+* Write `#ensure_session_token`
+  * This method makes sure that the user has a `session_token` set, setting one
+    if none exists
+
+## Phase 4: Check your work
+
+* Check your model against the solutions.
+* Try creating a user in the Rails console
+  * Make sure your validations work, and also make sure that you're storing
+    `password_digest` as an encrypted string
+
+Example testing code below:
+
+```ruby
+User.all # shows no users
+empty_gage = User.new
+empty_gage.save # rollback because of failed validations
+password_too_short_gage = User.new(username: 'gage', password: 'test')
+password_too_short_gage.save # rollback because of failed validations
+gage = User.new(username: 'gage', password: 'testing')
+gage.save # inserted into Users
+User.all #<ActiveRecord::Relation [#<User id: 1, username: "gage"...
+User.first.password_digest # shows a string of gibberish that you can't hack
+User.find_by_credentials('gage', 'testing') #<User:0x0000000112faf240 id: 1, username: "gage" ...
+```
+
+## Phase 5: Celebrate
+
+Congratulations! You have just written an important part of a Rails auth system.
\ No newline at end of file
diff --git a/rails/projects/art_share_api/README.md b/rails/projects/art_share_api/README.md
new file mode 100644
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+++ b/rails/projects/art_share_api/README.md
@@ -0,0 +1,297 @@
+# Art Share API, Part 1
+
+You're going to continue building on the API you built in the First Routes
+project. Your goal is to build an application to store, share, and comment on
+artwork, as well as search for users.
+
+Each user has a set of artworks that they own/control. These artworks can also
+be shared with other users. An artwork that has been shared with one or more
+other users will be visible to those users, but the artwork still 'belongs to'
+the original user.
+
+Although you will maintain this conceptual distinction between a user's own
+artworks vs. the artworks that have been shared with that user, you will
+eventually write an index method that will combine both types of a user's
+viewable artworks together so that you can see any art made by or shared with
+that user.
+
+## Learning goals
+
+By the end of this practice, you should be able to
+
+- Write Active Record models quickly
+- Write a private `xxxx_params` helper method
+- Write the five API RESTful controller actions
+- Test your API endpoints with Postman
+- Create and destroy join table records via controller actions
+- Create and use a nested route
+
+## Phase I: Data layer
+
+You almost always start with the data layer when you're thinking about adding
+functionality. Questions to consider include the following: What pieces of data
+are necessary to implement the functionality you need? What changes need to be
+made to the database schema? What models do you need? What associations and
+validations?
+
+In this first phase you're going to add the tables for users, artworks, and
+artwork shares. You are also going to write validations and associations linking
+them.
+
+### Instructions
+
+#### User
+
+For the `users` table you should have `name` and `email` columns from the First
+Routes project. Change your `User` model so that you have only one column:
+`username`. Write new migrations to accomplish this change. Enforce presence and
+uniqueness of `username` at both Active Record and DB levels.
+
+After you create each table and model below, make sure to test that your
+associations and validations are working before moving on to the next step. You
+want to be **_absolutely sure_** your code is working before you leave a phase;
+otherwise building your API endpoints will be needlessly complicated.
+
+#### Artwork
+
+For your `artworks` table you should have the following columns: `title`,
+`image_url`, and `artist_id`. All of these should be present, and you should
+ensure that the `image_url` is unique. Add the appropriate Active Record
+validations and DB constraints. Also add an index on `artist_id` so that you can
+quickly get all the artworks for a given artist.
+
+Ensure that a **single user** cannot have two artworks with the same title. Two
+different users, however, can have artworks with the same title. In other words,
+two separate artists could both have artworks of their own named "Untitled", but
+a single artist should not be able to have two pieces with that same title.
+
+This means that the `artist_id` and `title` **combination** must be unique.
+Enforce this at the DB and model levels. Here's some help for the [model
+validation][scoped-uniqueness]. To add the DB constraint, consider using a
+`unique` constraint on a composite index. (Make sure that you don't add
+unnecessary indexes. You should be able to accomplish everything in these
+instructions using only two indexes total on your `artworks` table.)
+
+Finally, add associations between `User` and `Artwork`. The association from
+`Artwork` to `User` should be called `artist`. Note that your column in the
+`artworks` table does not have to be `user_id` despite being a foreign key to
+the `users` table. In this case, `artist_id` is much more descriptive and
+therefore preferable.
+
+[scoped-uniqueness]:
+  http://guides.rubyonrails.org/active_record_validations.html#uniqueness
+
+#### ArtworkShare
+
+The `artwork_shares` table is a join table. Its whole purpose is to link a
+`User` (the person viewing the artwork) with an `Artwork`.
+
+You'll need `artwork_id` and `viewer_id` columns. Again, whenever possible,
+prefer columns names that are more semantic (i.e., more descriptive of the
+relationship).
+
+Ensure that both columns are present. Add the necessary validations /
+constraints. Ensure that a user cannot have a single artwork shared with them
+more than once. Also, add indexes to `ArtworkShare`'s foreign key columns for
+fast lookup, again making sure not to duplicate any indexes.
+
+**N.B.**: You almost always want to create indexes for foreign keys,
+particularly if those foreign keys will be used in a `has_many` or a `has_one`
+relationship. This is why the `references` column type includes an index by
+default.
+
+Add an association connecting an `ArtworkShare` to an `Artwork`. Add another
+association that will connect an `ArtworkShare` to a `User` (name this
+association `viewer`).
+
+Next, utilize the `ArtworkShare` join table to connect an `Artwork` to the
+`User`s that it has been shared with. The `shared_viewers` association on
+`Artwork` should connect to `User`s `through` the `ArtworkShare` model.
+`Artwork#shared_viewers` should return the set of users with whom an artwork has
+been shared.
+
+Finally, create a similar association that will connect a `User` to the
+`Artwork`s that have been shared with them. The `shared_artworks` association on
+the `User` should connect to `Artwork`s `through` the `ArtworkShare` model. This
+`User#shared_artworks` association should return the set of artworks that have
+been shared with that user, **not** the set of artworks that a user has shared
+with others.
+
+### Recap
+
+You should now have tables and models for `User`, `Artwork`, and `ArtworkShare`,
+as well as the relevant validations and associations.
+
+If you haven't already, now would be a good time to create some seed data in
+your __seeds.rb__ file. This is easier than creating seed data in the Rails
+console and, should you ever drop your database, will provide an easy way to
+re-populate your tables with testable data.
+
+## Phase II: Users and Artworks API
+
+You'll handle the API layer next. The API describes how you will **expose** your
+data and specifies how the outside world can interact with it. Today you'll be
+using the Postman web app to test your API endpoints. When debugging make sure
+to reference your Rails server log. It will provide you will valuable insight if
+anything goes wrong.
+
+### Instructions
+
+First, make sure the `User` controller actions you created in the previous
+project are all working. They should do the following:
+
+- `user_params` helper method  
+  This method should be private. It requires the key `:user` in params and
+  permits each of the user attributes as keys in the nested hash.
+
+  - Update the permitted attributes to reflect the changes you made to the
+    `User` model.  
+
+- `create` (POST `/users`)  
+  This action should use `user_params` to create a new `User` and `if user.save`
+  to check if validations passed. On error, it should render validation errors
+  using `user.errors.full_messages` and set the status code to
+  `unprocessable_entity` (or `422`).  
+
+  - (Optional) You could add a status of `:created` when rendering the new user.
+
+- `destroy` (DELETE `/users/:id`)  
+  This action should use the id in `params[:id]` to find the user and delete it
+  from the database by calling the [`destroy`] method on the user instance. Best
+  practice is then to render the destroyed user.
+
+  - Add `dependent: :destroy` to the `artworks` and `artwork_shares`
+    associations on `User` to ensure that the associated records will also be
+    destroyed.  
+  
+    **N.B.**: There is another Active Record method that removes objects from
+    your database, `delete`. This method, however, does not run callbacks such
+    as `dependent: :destroy` and is therefore **not** the method you want to
+    use.
+
+- `index` (GET `/users`)  
+  This action should render all the users in the database.
+
+- `show` (GET `/users/:id`)  
+  This action should render a single user, using the id in `params[:id]`.
+
+- `update` (PATCH `/users/:id`)  
+  This action should find the requested user, then use `update` with
+  `user_params` to do a mass-assignment update and save. It should render
+  validation errors using `user.errors.full_messages`. _Don't forget the status
+  code!_
+
+Now move to the __routes.rb__ file. You should already have routes for the
+`users` controller from the previous project. Do the following:
+
+- Comment out the individually-specified `users` routes.
+- Use `resources` with the `only:` option to restrict the available `users`
+  routes to the five actions listed above.
+
+Check your work by running `rails routes` in the terminal. You should see six
+routes in total. (Remember that Rails will generate both `patch` and `put`
+routes for the `update` action.)
+
+Next, create the `ArtworksController`. Build the same five actions and params
+helper method. Your code will look very similar, but practice this a second
+time.
+
+> **Hint**: For this project, do not write any authentication or authorization
+> logic. When creating a new `Artwork`, require that the uploader submits their
+> `artist_id`. This isn't secure because anyone could always take your
+> `artist_id` and upload new artworks in your name. For now, however, assume the
+> users of your service aren't malicious. :-)
+
+When you finish with the controller, go back to the __routes.rb__ file and add
+routes for those five `artworks` actions, just like you did for `users`.
+
+### Recap
+
+Congratulations! You should now have tables, models, controllers, and routes for
+users and artworks. Before moving on, test that your API endpoints are working
+with Postman. Then call over an instructor and explain your code.
+
+## Phase III: Sharing `Artworks`
+
+Now you're going to add routes and controllers for your `ArtworkShares`. The
+`artwork_shares` table is a join table, so while RESTful design patterns still
+apply, your `ArtworkShares` controller will look a little different from the
+controllers you just wrote. All you need to be able to do is share and unshare
+artworks. What controller actions do you think you'll need?
+
+Once you have sharing working, you'll refactor `ArtworksController#index` so
+that it returns artworks either belonging to or shared with a particular user.
+In order to make this work you'll need to pass in the `user_id` to your `index`
+action so you can filter for the appropriate works.
+
+### Instructions
+
+Add new `resources` routes and a controller for `ArtworkShare`. Include the
+following actions and associated routes.
+
+- `create` (POST `/artwork_shares`)  
+  You'll want to pass the `artwork_id` and the `viewer_id`. Use strong
+  parameters to access these values by writing an `artwork_share_params` helper
+  method that will filter out any parameter that is not an appropriate
+  `ArtworkShare` attribute.
+
+- `destroy` (DELETE `/artwork_shares/:id`)  
+  This un-shares an `Artwork` with a `User`. To delete a share, the user should
+  issue a DELETE to `/artwork_shares/123`, where `123` is the `id` of the
+  `ArtworkShare` to destroy.
+
+After you create an `ArtworkShare` record, you will want to return the record to
+the client. Do the same thing upon deletion of an `ArtworkShare` record. In
+other words, both of these routes should conventionally render the
+created/destroyed `ArtworkShare` as the response.
+
+You won't need any other `artwork_shares` routes, so use `only:` to restrict
+them.
+
+Use Postman to make sure that your controller's `create` and `destroy` actions
+work properly. Remember, your validations should prevent us from sharing the
+same artwork with the same user more than once.
+
+#### User's Artworks: Nested routes
+
+You want to be able to fetch the artworks of a particular user. Right now,
+however, a GET to `/artworks` returns all of the artworks in the system.
+
+Add a new, nested resource, `/users/:user_id/artworks`, so that you can get the
+artworks for a given user. You'll only need the `index` action for this. (If you
+need help setting up a nested route, see the [Rails guides][nested-routes].)
+
+You may remove the `index` action from the top-level `artworks` resource. This
+will modify your API so that users can't download all the artworks in the system
+at one time; they will be able to download artworks only on a per-user basis.
+For example, they could get user 1's artworks through `GET /users/1/artworks`,
+user 2's through `GET /users/2/artworks`, and so on.
+
+The nested resource will still hit `ArtworksController#index`. Rewrite this
+`index` action to return:
+
+- The artworks owned by a user  
+**AND**  
+- The artworks shared with the user
+
+Implementing this functionality requires a more complex database query, but you
+want to keep your controllers lean; the logic required for complex queries
+belongs more with the model. Accordingly, to implement this query, write an
+`artworks_for_user_id` class method in your `Artwork` model that you can then
+call from your controller, passing in the specified user's id. (You can access
+the specified user's id in the controller through `params[:user_id]` because
+`:user_id` is part of the nested route.)
+
+Use Postman to make sure your modified `index` action in the
+`ArtworksController` returns all artworks owned by or shared with a user.
+
+### Recap
+
+At this point in the project you should be able to create `ArtworkShares` with
+Postman. Artworks shared with a particular user should also be included in data
+returned by a `GET` request to `ArtworksController#index`.
+
+## Head to Part 2!
+
+[`destroy`]: https://guides.rubyonrails.org/active_record_basics.html#delete
+[nested-routes]: https://guides.rubyonrails.org/routing.html#nested-resources
diff --git a/rails/projects/art_share_api/README_part_two.md b/rails/projects/art_share_api/README_part_two.md
new file mode 100644
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@@ -0,0 +1,104 @@
+# Art Share API Part 2
+
+**Make sure to finish Phases I - III before continuing!**
+
+Before starting Phase IV, go through and add an `inverse_of` option to any
+associations where it is needed:
+
+* any `has_many` that involves a `foreign_key` option on either side of the
+  association
+* any `belongs_to` on a join model that is used in a `has_many :through`
+  association
+
+Be sure to continue adding `inverse_of` to any new associations that you write
+today when it is appropriate!
+
+## Phase IV: Comments
+
+Now it's time to add commenting functionality to your application so your users
+can comment on a piece of artwork. By the time you're done, you want to be able
+to retrieve both a specific user's comments as well as comments left on a
+specific artwork. To do this, you'll have your `CommentsController#index` method
+return comments based on the params provided by the request.
+
+### Instructions
+
+First create a `comments` table that has a foreign key for both author and
+artwork. You'll also want a `body` column that contains the text of the
+comment. On what columns should you add an index?
+
+Your users and artworks will both `have_many` comments. A comment should
+`belong_to` an author (the user who left that comment) and artwork. Write
+these associations now. Remember to include `dependent: :destroy` when
+necessary. For instance, when an artwork or user is removed from the
+database, you don't want their associated comments to persist.
+
+Before moving on test that these associations work.
+
+Once you know that your table and model have been set up correctly, it's time
+to make your controller. The `CommentsController` should have `create`,
+`destroy`, and `index` actions.
+
+In order to retrieve comments for an artwork or a user, you want your `index`
+action to handle some additional params. In particular, you want to be able to
+pass in a `user_id` or an `artwork_id`. By checking if either is present, you
+can then retrieve the comments just for that user or artwork. Update your
+`comment_params` accordingly.
+
+### Recap
+
+It should now be possible to make `GET` requests to `CommentsController#index`
+and, depending on the params provided, return either comments made by a
+particular user or comments made on a particular piece of artwork.
+
+## Phase V: Search
+
+Next add search functionality to your application so users can search for other
+users by name. To do this, you won't need to change any routes. You can just
+edit the `index` action in your `User` controller.
+
+In `UsersController#index` check if a `query` is present in the request params.
+If it is, use that query to filter the users returned by the `index` action. If
+there is no query, just return all users as usual.
+
+Discuss with your partner the best way to write your query method. Here's a
+[good place to start][postgres-search].
+
+## Bonus Phase I: Likes
+
+In this phase you'll implement likes using polymorphic associations. Users
+should be able to like both comments and artworks. Read these [Rails
+docs][polymorphic-associations] on polymorphic associations to get started.
+
+Then discuss with your partner how you plan to approach this feature. You'd like
+to be able to call associations on a user and return their liked comments and
+artworks. You also want to be able to call an association on comments and
+artworks to get the users who have liked them.
+
+Hint: You can declare a column of type `references` to be polymorphic from a
+model generator like this:
+
+```sh
+rails g model Like liker:references likeable:references{polymorphic}
+```
+
+You'll notice that the generator does not add a `foreign_key` constraint to the
+polymorphic reference. A polymorphic reference's ability to point to more than
+one table means that you cannot assign it a `foreign_key` constraint.
+
+## Bonus Phase II: Favorite Artworks
+
+Allow users to "favorite" artworks. This will require additional columns to
+artworks (for favoriting of artworks by their owner) and shared artworks (for
+favoriting of artworks shared to a user). Use a semantic custom route to
+accomplish this. [Hint.][more-restful-actions]
+
+## Bonus Phase III: Artwork Collections
+
+Finally, users should be able to add artworks to artwork collections. Allow
+each user to have many collections. Artworks can also belong to more than one
+collection. What sort of table will you need to make this work?
+
+[postgres-search]: https://www.postgresql.org/docs/current/functions-matching.html
+[polymorphic-associations]: http://guides.rubyonrails.org/association_basics.html#polymorphic-associations
+[more-restful-actions]: http://guides.rubyonrails.org/v7.0.3/routing.html#adding-more-restful-actions
diff --git a/rails/projects/first_routes/README-pt2.md b/rails/projects/first_routes/README-pt2.md
new file mode 100644
index 0000000..704ae03
--- /dev/null
+++ b/rails/projects/first_routes/README-pt2.md
@@ -0,0 +1,181 @@
+## Phase II: First request
+
+In this phase, you will build your first controller, launch your server, and
+make your first request.
+
+### First controller
+
+The router defines API endpoints (i.e., URL path/HTTP verb combinations) and
+records which controller and action to invoke for each one. Each API endpoint
+has a conventional meaning: **C**reate, **R**ead, **U**pdate, or **D**estroy a
+resource. (These actions are collectively known as _CRUD_.) The
+controllers and their actions are the ones actually doing the **CRUD**ing.
+
+Create your first controller by navigating to __app/controllers__ and creating
+a new file called __users_controller.rb__ containing the following skeleton:
+
+```rb
+# app/controllers/users_controller.rb
+
+class UsersController < ApplicationController
+
+end
+```
+
+Note that **controllers are always plural**; a controller manages requests that
+pertain to a collection of _resources_. A resource is generally anything that
+has a table in your database. In other words, it is anything in your application
+that you will be CRUDing.
+
+Controllers inherit from `ApplicationController`, which is a controller itself,
+but one that never actually handles any requests directly.
+`ApplicationController` is where you'd put helper methods that you want to share
+across all controllers. If you look in
+__controllers/application_controller.rb__, you will see that
+`ApplicationController` inherits from `ActionController::Base`.
+`ActionController::Base` provides all of the bells & whistles that Rails
+controllers have; it's a lot like `ActiveRecord::Base` in that respect. All of
+your controllers will inherit the features it provides since it is in the
+inheritance chain:
+
+```rb
+UsersController < ApplicationController < ActionController::Base
+```
+
+Now that you have some routes and a matching controller, you have everything you
+need to start handling requests.
+
+### First launch
+
+You have your API endpoints set up and they map to a controller that you've
+created. How do you actually start taking requests?
+
+```text
+% rails server
+=> Booting Puma
+=> Rails 7.0.2.2 application starting in development 
+=> Run `bin/rails server --help` for more startup options
+Puma starting in single mode...
+* Puma version: 5.6.2 (ruby 3.1.0-p0) ("Birdie's Version")
+*  Min threads: 5
+*  Max threads: 5
+*  Environment: development
+*          PID: 54618
+* Listening on http://127.0.0.1:3000
+* Listening on http://[::1]:3000
+Use Ctrl-C to stop
+```
+
+Rails ships with a web server called Puma.
+
+As you can see, it loads your application in _development_ mode (you'll learn
+about the other two modes--_production_ and _testing_--later) and listens for
+requests at `http://0.0.0.0:3000`. The last part, `:3000`, specifies the port it
+is listening on. Rails defaults to port 3000 in development. The domain
+`http://0.0.0.0` can be accessed from your browser simply as `http://localhost`.
+
+In your browser, navigate to `http://localhost:3000`. Voilà! A running Rails app
+with what will become a very familiar index page.
+
+### First request
+
+Postman should already be installed, but if not, go ahead and [install
+it][postman].
+
+Try to get a list of all your users, i.e., your _users index_. This means you
+need to make a request that matches the HTTP verb and URL path that routes to
+`UsersController#index`. If you run `rails routes`, you can see this is a
+`GET` request to `/users`. Go ahead and make that request with Postman. (Make
+sure to keep your rails server running in a terminal tab!)
+
+Okay, that didn't work. Why not?
+
+The server log will be where you'll go to see what's going on in your
+application. All the `puts` and `p` statements in your application will also go
+to the server log. **Always look at the server log**; this is an essential
+debugging technique. You'll see what some of the most important information is
+in just a second. Here's what you see in the log:
+
+```text
+Started GET "/users" for ::1 at 2022-02-21 12:17:40 -0500
+  ActiveRecord::SchemaMigration Pluck (1.3ms)  SELECT "schema_migrations"."version" FROM "schema_migrations" ORDER BY "schema_migrations"."version" ASC
+  
+AbstractController::ActionNotFound (The action 'index' could not be found for UsersController):
+...
+```
+
+> Note: The `ActiveRecord::SchemaMigration` line will appear only for the first
+> request to the server; if it's not there, don't worry about it!
+
+Looks like a request came in; what's the error? It seems like it's complaining
+that you don't actually have an `index` action setup in your `UsersController`.
+Note that your application looked for an `index` action because the router
+specified that a `GET` request to `/users` maps to `users#index`, which is the
+Rails shorthand for `UsersController#index`.
+
+Fix the problem by adding an empty `index` action to your `UsersController`:
+
+```ruby
+# app/controllers/users_controller.rb
+
+class UsersController < ApplicationController
+  def index
+  end
+end
+```
+
+Make the request in Postman again. It fails again, so look at the log:
+
+```text
+Started GET "/users" for ::1 at 2022-02-21 12:22:35 -0500
+Processing by UsersController#index as */*
+No template found for UsersController#index, rendering head :no_content
+Completed 204 No Content in 0ms (ActiveRecord: 0.0ms | Allocations: 85)
+...
+```
+
+> Note: If you make a `GET` request through a browser at this point--i.e., if
+> you go to `http://localhost:3000/users`--you will get a `406 Not Acceptable`
+> status code.
+
+This time, it's complaining that there's a missing template. Wait a minute; you
+never called `render`. Why is it trying to look for a template at all? Because
+in the absence of an explicit `render` statement, your controller will by
+default try to render a template with the same name as the controller action.
+In this case, it was looking for a template called __index.html.erb__ in
+__app/views/users__.
+
+You're not going to deal with views and templates just yet. To get rid of this
+error, just add a simple render:
+
+```ruby
+# app/controllers/users_controller.rb
+
+class UsersController < ApplicationController
+  def index
+    render plain: "I'm in the index action!"
+  end
+end
+```
+
+Try again. It should work! Now take a look at the server log.
+
+```text
+Started GET "/users" for ::1 at 2022-02-21 12:28:24 -0500
+Processing by UsersController#index as */*
+  Rendering text template
+  Rendered text template (Duration: 0.0ms | Allocations: 9)
+Completed 200 OK in 3ms (Views: 2.8ms | Allocations: 684)
+```
+
+For every request, the server will tell you which controller and action is
+processing it. In this case, it was the `UsersController`'s `index` action.
+
+Woohoo! Your Postman request should have returned the string, "I'm in the index
+action!" Victory is yours. Congratulations on successfully setting up, making,
+and processing your first Rails request!
+
+Now head to [Phase III](README-pt3.md), where you will get familiar with the various types of
+parameters.
+
+[postman]: https://www.getpostman.com/
diff --git a/rails/projects/first_routes/README-pt3.md b/rails/projects/first_routes/README-pt3.md
new file mode 100644
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--- /dev/null
+++ b/rails/projects/first_routes/README-pt3.md
@@ -0,0 +1,156 @@
+## Phase III: Playing with parameters
+
+Now you're going to focus on how data comes into your controllers from the
+outside world.
+
+The key method here is `#params`. `#params` is a method provided by
+`ActionController::Base` that returns a Hash-like object of all the parameters
+available. The parameters are compiled by the router and are sourced from three
+places:
+
+1. Route parameters (e.g., the `:id` from `/users/:id`)
+2. A query string (i.e., the part of the URL after the `?`: `?key=value`)
+3. `POST`/`PATCH`/`PUT` request data (i.e., the body of an HTTP request)
+
+Make some `GET` requests to `/users` that include some key/value pairs in the
+query string, e.g., `/users?fav_food=pizza` or `/users?admin=true`.
+
+Check out the server log and notice that it logs how the parameters are coming
+in:
+
+```text
+Started GET "/users?fav_food=pizza" for ::1 at 2022-02-21 12:32:02 -0500
+Processing by UsersController#index as */*
+  Parameters: {"fav_food"=>"pizza"}
+  Rendering text template
+  Rendered text template (Duration: 0.5ms | Allocations: 3)
+Completed 200 OK in 3ms (Views: 2.4ms | Allocations: 192)
+```
+
+Now make some `POST` requests to `/users` playing around with `POST` data and
+see how the parameters come in. This means putting the data in the request body
+instead of in the query string. Click on the 'Body' tab in Postman and enter the
+key/value pairs there. Make sure to change the HTTP verb to `POST`.
+
+Think about what controller action you will hit when you make a `POST` request
+to `/users` (check your routes again). Once again, you'll get the error that
+this action is not defined on your `UsersController`:
+
+```text
+Started POST "/users" for ::1 at 2022-02-21 12:36:07 -0500
+  
+AbstractController::ActionNotFound (The action 'create' could not be found for UsersController):
+...
+```
+
+Go ahead and add that method to the controller. Again, if you don't explicitly
+render or redirect, Rails is going to try to render the template with the same
+name; it's going to look for __create.html.erb__ in your __app/views/users__
+folder, which you don't have. To prevent this, you need to explicitly render
+something simple back. In this case, render the params that came in with the
+request. You can `render json:`, which will automatically call `to_json` on the
+object you're rendering (here, your `params`) and package it up for you so that
+it can be sent back with the response:
+
+```ruby
+# app/controllers/users_controller.rb
+
+class UsersController < ApplicationController
+  def create
+    render json: params
+  end
+end
+```
+
+Try making the request in Postman again. You should see the right response now!
+
+```json
+{
+  "fav_food": "pizza",
+  "controller": "users",
+  "action": "create"
+}
+```
+
+Okay, you've seen params come from the query string and the request body. Now
+you will send them from the third and final place they can come from: the route
+params.
+
+When you include `show`, `delete`, and `update` routes in your `resources`,
+Rails constructs _Uniform Resource Identifier (URI) patterns_ for these that
+include a _dynamic segment_ matcher. A URL path is split into _segments_ by
+`/`s. A _dynamic segment_ is any segment of the URI pattern that begins with a
+`:`. If you look at your routes, you can see these wherever the URI pattern is
+`users/:id(format)`. The `:id` indicates that the router will match anything put
+into that segment of the URL and save it in `params` under the key `id`.
+
+Try making a `GET` request to `/users/:id`. In Postman, this means setting
+the URL to something like '/users/2', where 2 is the `id` of the `User` you want
+to see.
+
+Once again, you get the same error. You are matching the `UsersController#show`
+route, but you don't have that action defined on the controller. Go ahead and
+add it, and once again `render json: params`. Now try the request again. You see
+the `:id` matcher saved the `2` from your URL in the params!
+
+```json
+{
+  "controller": "users",
+  "action": "show",
+  "id": "2"
+}
+```
+
+> Note: If you forget to change your verb back to `GET` in Postman, you will get
+> an error because there is no `POST` route with the URI pattern `users/:id`:
+
+```text
+Started POST "/users/2" for ::1 at 2022-02-22 11:53:43 -0500
+  
+ActionController::RoutingError (No route matches [POST] "/users/2"):
+```
+
+> Just change the verb to `GET` and you should be good to go!
+
+### Nesting parameters
+
+Notice how all of your parameters come in at the top level of `params`. What if
+you want to structure it a bit differently so that certain parameters come in
+nested under others (i.e., a hash within a hash), like so:
+
+```json
+{
+  "id": 5,
+  "some_category": {
+    "a_key": "another value",
+    "a_second_key": "yet another value",
+    "inner_inner_hash": {
+      "key": "value"
+    }
+  },
+  "something_else": "aaahhhhh"
+}
+```
+
+Here's how you would accomplish this:
+
+```html
+<!-- in Postman's "Body" tab -->
+some_category[a_key]: another value
+some_category[a_second_key]: yet another value
+some_category[inner_inner_hash][key]: value
+something_else: aaahhhhh
+
+<!-- in the query string -->
+'/users?some_category[a_key]=another+value&some_category[a_second_key]=yet+another+value&some_category[inner_inner_hash][key]=value&something_else=aaahhhhh'
+```
+
+If you follow this bracket notation, Rails will nest the parameters for you. The
+rule is that the keys in brackets get nested deeper in `params`.
+
+Try it out a few times with both `GET` and `POST` requests. Make sure you're
+looking at the parameters that come in with the request, either through your
+controller action's rendering them back as JSON to Postman or in the server
+logs.
+
+In the [fourth and final phase](README-pt4.md), you will add models to the mix.
diff --git a/rails/projects/first_routes/README-pt4.md b/rails/projects/first_routes/README-pt4.md
new file mode 100644
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--- /dev/null
+++ b/rails/projects/first_routes/README-pt4.md
@@ -0,0 +1,122 @@
+## Phase IV: Using models
+
+By this point you know how to set up routes, how to set up matching controller
+actions, how to send and process incoming data through parameters, and how to
+render something back to the requester. Now you will mix in some models.
+
+Build a `User` model with name and email. Write a migration to add columns for
+`name` and `email` with `null: false` constraints. Migrate your database and add
+validations for presence of name and email. Add a couple users through the
+console. (Make sure you save them to the database!)
+
+In your `UsersController#index`, fetch all the users from the database and
+render them as JSON. Remember that when you hand `render json:` anything, it
+automatically calls `to_json` on it for you.
+
+Make the request in Postman and make sure you're getting the right JSON back.
+Check your server log and note that the SQL that ran is logged there for you.
+All SQL queries your app makes will show up in the server log - yet another
+useful piece of information that the log contains.
+
+```text
+Started GET "/users" for ::1 at 2022-02-22 14:19:58 -0500
+Processing by UsersController#index as */*
+  User Load (0.3ms)  SELECT "users".* FROM "users"
+  ↳ app/controllers/users_controller.rb:6:in `index'
+Completed 200 OK in 5ms (Views: 4.6ms | ActiveRecord: 0.3ms | Allocations: 992)
+```
+
+Congrats! Applications, and especially web APIs, are all about connecting data
+in your database with the outside world. You've just done that.
+
+### Creating a `User` through the API
+
+Now you can provide a way to create a new user through the API. Below is a start
+for a `create` action. Note that you are not using an instance variable for
+`user`: you will see why instance variables are very useful when you start
+working with views, but they aren't strictly necessary for the controller to
+work with models or to interact with the database.
+
+```ruby
+# app/controller/users_controller.rb
+
+def create
+  user = User.new(params.require(:user).permit(:user_attributes_here))
+  # replace the `user_attributes_here` with the actual attribute keys
+  user.save!
+  render json: user
+end
+```
+
+Go ahead and make a `POST` request to create a new user with Postman. Make sure
+to nest your params correctly! By calling `.require(:user)` on `params`, the
+`UsersController#create` method is requiring that all user params be nested
+under the key of `user` in `params`.
+
+This _namespacing_ of all user params under `user` leverages mass assignment to
+set all the uploaded attributes at once. This is an extremely common Rails
+pattern: pretty much every time your request body includes attributes for
+creating or updating a resource, you will nest them within an inner hash to use
+for mass assignment.
+
+### Handling submission errors
+
+What if the user doesn't upload valid parameters for a new `User`? Try making
+the same request as before but with no `email` param, only a `name`.
+
+This doesn't upload the required email attribute. The controller will create a
+`User` object, but when it calls `save!` the validation will fail and an error
+will be raised.
+
+To inform the user of what went wrong, it is typical to send back error
+messages. Modify your controller code to send back the errors as JSON in
+the event of a failure:
+
+```ruby
+# app/controller/users_controller.rb
+
+def create
+  user = User.new(params.require(:user).permit(:name, :email))
+  if user.save
+    render json: user
+  else
+    render json: user.errors.full_messages, status: :unprocessable_entity
+  end
+end
+```
+
+Note that if the save of the user fails, you send the errors back to the client.
+You also set the status code. By default, the status code will be 200 (OK); if
+something has gone wrong, use a non-200 code to indicate this. In this case, you
+should return a status code of 422. Rails gives us names for these various
+status codes so that the code is a bit more semantic. Here is a list of the
+[Rails status code names][rails-codes].
+
+Make the request again. You should see the error message displayed in Postman.
+
+Now build some other controller actions:
+
+- `show`
+- `update` (you'll want to use `ActiveRecord::Base#update`)
+- `destroy`
+
+Think about what each action's purpose is, what data is coming in (params), what
+your controller needs to do with the model, and what it ultimately should
+render. Test each of them out in Postman as you go!
+
+While you're at it, try refactoring the `params[...].permit(...)` stuff into its
+own (private) method. If you need an example, check out the controllers
+reading.
+
+## What you've learned
+
+In this project, you learned how to create the RESTful routes, both by using the
+`resources` helper and by writing out the route-matching syntax. You then built
+out the corresponding actions in your controller, using requests from Postman
+and the browser to test your code. You also learned about the three different
+ways that parameters can be passed into your application (i.e., query string,
+body, and route). Finally, you learned how to nest your params under an
+appropriate namespace, how to use that namespace in mass assignments, and how to
+respond to a request by rendering data or errors in JSON.  
+
+[rails-codes]: http://guides.rubyonrails.org/layouts_and_rendering.html#the-status-option
diff --git a/rails/projects/first_routes/README.md b/rails/projects/first_routes/README.md
new file mode 100644
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--- /dev/null
+++ b/rails/projects/first_routes/README.md
@@ -0,0 +1,119 @@
+# First Routes & Controllers
+
+In this project you'll start playing with Rails routing.
+
+## Learning goals
+
+- Be able to create routes in __config/routes.rb__
+- Be able to read and understand Rails server error messages
+- Know the three places that `params` come from
+- Be able to nest query parameters
+- Be able to write controller actions that read from and write to the database
+- Know how and when to render errors
+
+## Rails Diagram
+
+As you work through the project, revisit this diagram at each phase and discuss
+with your pair how the code you've written so far fits into the relationships
+displayed here.
+
+- ![Rails Diagram][diagram]
+
+## Phase 0: Setup
+
+To start, generate a new, blank Rails project: `rails new <project_name>
+<flags>`. Don't forget to add flags to:
+
+1. Set PostgreSQL as the database,
+2. Skip setting up the project as a Git repo,
+3. Skip setting up the Rails testing framework, and
+4. Install a minimal build.
+
+Grab the __.gitignore__ and __.gitattributes__ files from the starter repo at
+the `Download Project` button below and copy them into the root directory of
+your project.
+
+If you prefer to use `byebug` instead of `debug` as your debugger, then replace
+`debug` with `byebug` in your Gemfile. Add any other gems you want to install
+(e.g., `annotate`, `pry-rails`, `better_errors`, and `binding_of_caller`).  If
+you make any changes to your Gemfile, run `bundle install` to incorporate them
+into your project.
+
+Next, set up your Postgres database by running `rails db:create`.
+
+By default, Rails protects against a type of attack known as Cross-Site Request
+Forgery (CSRF) by checking that non-GET requests include a valid _authenticity
+token_. Don't worry about that for now. For this particular assignment, go to
+__config/application.rb__. Right after the `config.load_defaults X.X` line, add:
+
+```rb
+config.action_controller.default_protect_from_forgery = false
+```
+
+Adding this line ensures that you won't need to include an authenticity token in
+your `POST` request params; you'll learn what that means later. (Once you know
+how to add authenticity tokens to your requests, you won't need to add this line
+to your projects.)
+
+## Phase I: First routes
+
+You're now ready to generate your first routes! Go to __config/routes.rb__ and
+add the following line inside the `Rails.application.routes.draw` block:
+
+```ruby
+resources :users
+```
+
+Remember that this one line actually generates **eight routes** for you. Run
+`rails routes` to see what those routes are.
+
+Woohoo! You've set up your first eight _API endpoints_. Each route you have is
+an API endpoint, which encapsulates a single action your app can take.
+
+Look again at the left-most column, which displays the prefix for a route. Rails
+uses these prefixes to generate the helper methods `<prefix>_path` and
+`<prefix>_url` that you can use in your code to generate a route's path and url,
+respectively. In addition to making your code more readable, these methods also
+make it easier to maintain your code: if a route changes, the helper methods
+will automatically generate the new path/url everywhere they appear. You will
+learn more about these helper methods and their uses later.
+
+You may notice that some of the routes seem to be missing prefixes. This is
+because prefixes are based on a route's **path**, not its **verb**. All routes
+with the same path will share the same prefix, meaning that a prefix does not
+need to be listed more than once for any given path. So, e.g., the `index`
+route--a `GET` request to `users/`--and the `create` route--a `POST` request to
+`users/`--will both have the prefix `users`, even though the prefix only appears
+next to the `index` route.
+
+The ease with which Rails converts that one `resources` line into eight routes
+might seem like magic, but you can do it too. Try the following:
+
+- Comment out the `resources :users` line.
+- Write out the eight routes using the route 'matching' syntax. For example:
+  `get 'users/:id', to: 'users#show', as: 'user'`.
+
+Run `rails routes` again and check that the routes you've written match the
+routes generated by the `resources` helper exactly. __N.B.__: you'll probably
+see some differences in the prefixes listed for your routes. Again, try to match
+the `resources` output exactly. You can add a prefix to a route by using the
+`as` option. For example: `get 'users/new', to: 'users#new', as: 'new_user'`.
+Remember, too, that you don't need to specify a prefix more than once for any
+given **path**.
+
+What do these routes actually do? Starting your Rails server creates an instance
+of a _router_. This router holds instances of the _routes_ that are defined in
+your __routes.rb__ file. When a request comes in, the router tries to match a
+route based on the **HTTP method** and the **URL path**. (It does this with a
+_regular expression_, if you know what that is already.) The **first** matched
+route then instantiates an instance of the specified controller and calls the
+specified action on it.
+
+You now have the initial routes and endpoints necessary to manage a `User`
+resource. Notice, though, that your routes point to a `UsersController`, which
+you don't actually have yet. Nor do you have a `User` model. You'll add the
+model later. (Soon!)
+
+Next up: [the controller!](README-pt2.md)
+
+[diagram]: https://assets.aaonline.io/fullstack/rails/assets/rails_diagram.png
diff --git a/rails/projects/goal_app/.gitattributes b/rails/projects/goal_app/.gitattributes
new file mode 100644
index 0000000..34fb547
--- /dev/null
+++ b/rails/projects/goal_app/.gitattributes
@@ -0,0 +1,7 @@
+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
\ No newline at end of file
diff --git a/rails/projects/goal_app/.gitignore b/rails/projects/goal_app/.gitignore
new file mode 100644
index 0000000..4f0da6f
--- /dev/null
+++ b/rails/projects/goal_app/.gitignore
@@ -0,0 +1,26 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
\ No newline at end of file
diff --git a/rails/projects/goal_app/README-ph2-3.md b/rails/projects/goal_app/README-ph2-3.md
new file mode 100644
index 0000000..dca5d3e
--- /dev/null
+++ b/rails/projects/goal_app/README-ph2-3.md
@@ -0,0 +1,121 @@
+# Goal App (Phases II-III, Bonus)
+
+[Live Demo]
+
+[Live Demo]: https://aa-goal-app.herokuapp.com/
+
+## Phase II: Goals
+
+You are now ready to implement the 'goals' feature. Users should be able to CRUD
+(create, read, update, and delete) their goals. Goals can also be private or
+public - other users should not see 'private' goals, but a user should see all
+of their own goals. Finally, think of a way for users to track which goals are
+completed.
+
+Create model, request (covering routes, controller, and views), and Capybara
+system specs to ensure your 'goals' feature is fully tested. Write the tests
+first: red to green!
+
+Write the system specs first because they will force you to think about what
+your app should do at a high level. Remember that system tests especially should
+focus on behavior rather than implementation details. For example, your
+completion test should work as long as users can track their goal completion,
+regardless of how the code behind that feature works. Use a separate spec file
+for each feature mentioned above: one for CRUD, one for privacy, and one for
+completion.  
+
+As you think about what tests to write and how to implement them, keep the
+following in mind:
+
+1. You've already set up your FactoryBot factory to generate users; when you
+   need a user instance, you might as well use it!
+2. Consider setting up a basic `Goal` factory.
+3. Many features work differently depending on whether or not a user is logged
+   in. With such features, your specs need to cover both cases. Same valid and
+   invalid parameters.
+4. Don't forget about your `log_in_as` and `sign_up_as` helper methods when
+   writing your system tests.
+5. Capybara methods like `log_in_as` will not work in request specs, but you
+   will still need to have a logged-in user for some request specs. That's okay!
+   You already know how to write a `log_in_as` method. Repeat what you did for
+   the Capybara version. In this version, however, you don't have to worry about
+   filling in forms and clicking buttons. Just send a request to the correct url
+   with appropriate `params`.
+6. Keep your spec files clean by creating other methods in your helper modules.
+7. If you want to see what the webpage looks like during one of your Capybara
+   tests, call `save_and_open_page`. (This requires that you have installed the
+   `launchy` gem.)
+
+## Phase III: Comment ALL the things
+
+You need to let a user add comments. Imagine all the helpful words of
+encouragement that other users could add to a goal. Ok, now here's the crazy
+part. You **also** want to be able to comment on users. This way a user's show
+page will have comments, and each goal will also have comments.
+
+For now, you will implement the comments using two different tables,
+`UserComment` and `GoalComment`. In a few days, when you have learned about
+polymorphic associations and concerns, you will then return to this project and
+refactor your comment code DRYing it up significantly.
+
+The best part about this refactor? The tests that you write today will ensure
+that you do it correctly! That's the great benefit of testing behavior instead
+of implementation details.
+
+### The two-table approach
+
+As you implement this, write some high-level system tests to make sure your
+comments work as expected. (Put all comment-related tests in a single file,
+__comment_spec.rb__.) Use the Red-Green-Refactor approach. Remember, one test at
+a time!
+
+Your tests will need to cover comments on both users and goals at a minimum. You
+can likely use the same tests in each context. For a situation like this, you
+can use [shared examples] to keep your code DRY. Start by defining the shared
+code:
+
+```ruby
+shared_examples "comment" do
+  it "should have a form for adding a new comment" do
+    # ...
+  end
+  # ...
+end
+```
+
+To invoke this example in a specific context, you then use `it_behaves_like`:
+
+```rb
+describe "user profile comment" do
+  visit user_url(user_hello_world)
+  it_behaves_like "comment"
+end
+```
+
+> **NOTE:** The `shared_examples` must be defined before a context invokes them.
+
+Also bear in mind that you're about to replace the feature code, so it's super
+important to test **behavior**, not **implementation**.
+
+## Bonus
+
+- Cheers: Users can give cheers for the goals of other users. Set a limit on the
+  total number of cheers they can award--say, 12--so they have to be selective.
+- Write unit tests for your other models using
+  [shoulda-matchers][shoulda-matchers] and
+  [factory_bot_rails][factory-bot-rails].
+- Style your app.
+
+## What you've learned
+
+In this practice, you learned how to do Test Driven Development:
+Red-Green-Refactor! Along the way, you also learned how to write unit tests (for
+your models), request tests (for your routes, controllers, and views), and
+system tests (for the user experience) using a variety of testing-related
+packages: Spring, Guard, RSpec, Shoulda Matchers, FactoryBot, Faker, and
+Capybara. Finally, you learned the importance of implementing one feature at a
+time and testing behavior rather than implementation.
+
+[shared examples]: https://relishapp.com/rspec/rspec-core/docs/example-groups/shared-examples
+[shoulda-matchers]: https://github.com/thoughtbot/shoulda-matchers
+[factory-bot-rails]: https://github.com/thoughtbot/factory_bot_rails
\ No newline at end of file
diff --git a/rails/projects/goal_app/README.md b/rails/projects/goal_app/README.md
new file mode 100644
index 0000000..3324d4d
--- /dev/null
+++ b/rails/projects/goal_app/README.md
@@ -0,0 +1,394 @@
+# Goal App
+
+[Live Demo]
+
+Today you're going to create an app to help people keep track of goals they set
+for themselves. You'll also add a social element where people can view and
+comment on each other's goals, harnessing the power of **social** to motivate
+your users toward their hopes and dreams.
+
+[Live Demo]: https://aa-goal-app.herokuapp.com/
+
+## Learning goals
+
+By the end of this practice, you should be able to
+
+- Write model and request tests using RSpec
+- Write system tests using Capybara and RSpec
+- Determine what and when to test
+- Test **behavior** rather than **implementation**
+- Develop one feature at a time (the 'slices' approach)
+
+## Setup
+
+You will begin by creating a new Rails app, but this time you will create the
+app a bit differently because you want the System Test components installed.
+Pick a name for your app that is not "goal", "goals", or anything else that will
+conflict with a model class name, something like `goal-app`. Make a directory
+with that name and `cd` into it.
+
+In this new directory, create a file __options.rc__ (or whatever you want; the
+name doesn't matter). List the following options inside:
+
+```sh
+--skip-action-cable
+--skip-action-mailer
+--skip-action-mailbox
+--skip-action-text
+--skip-active-job
+--skip-active-storage
+--skip-bootsnap
+--skip-dev-gems
+--skip-javascript
+--skip-jbuilder
+--skip-hotwire
+```
+
+This includes all the normal options (minus `--skip-system-test`) that are
+included under the hood when you create an app with the `--minimal` flag. Now
+create your app using the `--rc` flag:
+
+```sh
+rails new . --rc=options.rc -G -d=postgresql
+```
+
+Using the `.` in place of an app's name tells Rails to create the new app in the
+current directory instead of making a new one. Rails will accordingly use the
+name of the current directory for the app's name.
+
+Remember **NOT** to include the `-T` flag as it would affect the System Test
+installation. Also, skip the `-G` flag if you are not creating this app inside
+a pre-existing git repository. Assuming that you do use `-G`, you can grab
+__.gitattributes__ and __.gitignore__ files from the starter repo accessed
+through the `Download Project` button below.
+
+You will need authentication in this project, so uncomment `gem "bcrypt"` in
+your __Gemfile__. Then follow the steps in the "Testing Setup Summary" reading
+to set up the various testing-related packages that you read about last night:
+
+- RSpec
+- FactoryBot
+- Faker
+- Shoulda Matchers
+- Capybara
+- Spring
+- Guard
+
+Finally, create your database.
+
+## Phase I: User creation and login
+
+Today's main focus will be Capybara system tests, but you will write some
+model and controller/request specs as an RSpec warm up. In this phase, you will
+build the models and controllers needed for user creation and authentication.
+But don't write out your `User` model just yet: you are going to write this app
+TDD style!
+
+### Model and controller tests
+
+Begin by generating and migrating an appropriate `User` model. (Keep it simple:
+only have a user give a `username` and `password`.) Then write your specs before
+you start to fill in the model.
+
+Your model specs should test your model's validations, associations, and public
+methods (e.g., `User::find_by_credentials`). (Typically, you only test public
+methods; you test private methods by making sure the public ones work.)
+
+Use [Shoulda Matchers] to write tests for each of the validations in your `User`
+model. Remember to have your Matchers account for any additional options that
+your validations check (e.g., minimum length).
+
+> **Note:** If you implement `session_token` so that it never returns `nil`,
+> Should Matchers will not be able to validate its presence. Depending on how
+> you implement `password_digest`, Should Matchers could also have trouble
+> validating its presence. You'll likely need to find other ways to test these
+> two attributes.
+
+You initially won't have any associations written on your user model; go back
+and fill these in as you create other relevant models. Refer to the "Testing
+Models With RSpec" reading as needed.
+
+> **Tip:** `bundle exec annotate --models` will annotate your model files in
+> __app/models__, __spec/models__, and __spec/factories__.
+
+Next, write request tests for each action you will need in your
+`UsersController`. (Don't worry about editing or deleting a user.) Refer to the
+"Testing Requests With RSpec" reading as needed.
+
+> **Tip:** `rails g rspec:request User` will generate the appropriate request
+> spec file.
+
+Run your specs and watch them fail. Now, implement `User` and `UsersController`
+and experience the joy of turning your specs green! (Remember that request specs
+also involve the routes and the rendered views!) Running `bundle exec guard`
+will cause your tests to run automatically as you edit your files.
+
+> **Note:** If you `expect(response.body)` to include a string that contains an
+> apostrophe (e.g., `"Username can't be blank"`), it will always fail, even if
+> that exact text **seems** to appear on the page. The problem has to do with
+> how HTML handles the apostrophe. You can solve the problem by `unescape`ing
+> the HTML like this:
+
+  ```rb
+  expect(CGI.unescapeHTML(response.body)).to include("Username can't be blank")
+  ```
+
+Skip the other model and controller specs. Go ahead and finish building out your
+authentication functionality so you can move on to new material: writing
+Capybara system tests!
+
+[Shoulda Matchers]: https://matchers.shoulda.io/docs/v5.1.0/#activemodel-matchers
+
+### System tests
+
+For the remainder of the day, you'll be writing [system tests] utilizing the
+joyous creature that is Capybara!
+
+Start by writing system tests for authentication. Write only one test at a time
+before implementing the corresponding feature logic. (Tests should fail at the
+beginning.) Don't move on to another feature until you are confident that
+your current feature is working well.
+
+If you generate the spec file with the Rails generator--`rails g rspec:system
+auth`--it will produce the following skeleton:
+
+```rb
+# spec/system/auths_spec.rb
+
+require 'rails_helper'
+
+RSpec.describe "Auths", type: :system do
+  before do
+    driven_by(:rack_test)
+  end
+
+  pending "add some scenarios (or delete) #{__FILE__}"
+end
+```
+
+Note that the generator pluralizes the argument you pass for the name of your
+test, so you end up with an __auths_spec.rb__ and `RSpec.describe "Auths"`.
+While that is great if you are testing something like `goals`, `auths` is a
+little awkward; feel free to make it singular again in both the filename and the
+test description.
+
+You can also just create the spec file yourself. If you do, however, note these
+elements in the skeleton above:
+
+1. You need to include `require 'rails_helper'` at the top.
+
+2. Specifying that these tests are of `type: :system` is good practice, but it
+   is not strictly necessary as long as this file is in the __spec/system__
+   folder and `config.infer_spec_type_from_file_location!` appears in your RSpec
+   configuration in __spec/rails_helper.rb__. (It appears by default; go ahead
+   and check, it's there!)
+
+3. You do need to include
+
+   ```rb
+   before do
+    driven_by(:rack_test)
+   end
+   ```
+
+   This changes the driver from the default `:selenium` to `:rack_test`.
+   Selenium will open a browser to run every test. This is helpful if your tests
+   need to run some JavaScript in the browser, but tests for this app won't need
+   that functionality.
+
+4. The `pending` line is just a placeholder that will show up when you run your
+   tests as a reminder that you still need to write tests. It is not required
+   and, if included, should be deleted once you have actually written some
+   tests.
+
+Now that your file is set up, here is a basic outline to get you started on
+authorization specs:
+
+```ruby
+# spec/system/auth_spec.rb
+
+RSpec.describe "Auth", type: :system do
+  before do
+    driven_by(:rack_test)
+  end
+
+  describe "the sign up process" do
+    it "has a new user page"
+    it "shows username on the homepage after signup"
+  end
+
+  describe "logging in" do
+    it "shows username on the homepage after login"
+  end
+
+  describe "logging out" do
+    it "begins with a logged out state"
+    it "doesn't show username on the homepage after logout"
+  end
+end
+```
+
+Fill in the missing test logic, one test at a time. Remember to think like a
+user: what page do you need to visit, what form fields need to be filled in,
+what buttons clicked, what should you see on the page, and so on. Refer to the
+[Capybara docs] for a list of methods you can use. To help with creating users
+to manipulate, consider using FactoryBot and Faker.
+
+[system tests]: https://relishapp.com/rspec/rspec-rails/docs/system-specs/system-spec
+[Capybara docs]: https://rubydoc.info/github/teamcapybara/capybara/master#the-dsl
+
+### FactoryBot and Faker
+
+At some point in your authorization tests, you are going to need to create a
+user. You could do this manually in your test file, but this can get cumbersome,
+especially if 1) your models have many attributes and 2) you need multiple
+instances. Your `User` model is not so large here, but try using FactoryBot
+anyway just for the practice.
+
+To build a user factory, go to the __spec/factories__ folder. If you used the
+Rails model generator to generate your `User` model, then you should already
+have a __users.rb__ file in there. (If not, just create one.) The generator also
+supplies a basic skeleton for a `User` factory that will probably look something
+like this:
+
+```ruby
+FactoryBot.define do
+  factory :user do
+    username { "MyString" }
+    session_token { "MyString" }
+    password_digest { "MyString" }
+  end
+end
+```
+
+Your `User` takes a `password` rather than a `password_digest`, and you don't
+need to pass in a `session_token`, so you can replace those lines with one for
+`password`. `MyString` is also not a very apt `username`; grab a `user_name`
+from Faker's `Internet` generator instead:
+
+```ruby
+FactoryBot.define do
+  factory :user do
+    username { Faker::Internet.unique.user_name }
+    password { "password" }
+  end
+end
+```
+
+> **Note:** You need to add `unique` to the Faker call to ensure that the users
+> produced by this factory will not violate the `uniqueness` validation on
+> `username`. If uniqueness did not matter, you could omit it:
+> `Faker::Internet.user_name`.
+
+This factory will create a random user, but it also might be helpful to have a
+factory that would produce a user whose details were known. For example, you
+could create a `hello_world` user like this:
+
+```rb
+FactoryBot.define do
+  factory :user do
+    username { Faker::Internet.unique.user_name }
+    password { "password" }
+
+    factory :user_hw do
+      username { "hello_world" }
+    end
+  end
+end
+```
+
+By nesting the `:user_hw` factory inside the `:user` factory, you enable it to
+inherit any characteristics that are not overwritten. Building a `:user_hw`
+would accordingly produce a `User` whose `username` is `hello_world` and whose
+`password` is `password`.
+
+To use these factories, just call `FactoryBot.build(:user_hw)` (will not save
+the resulting user to the database) or `FactoryBot.create(:user_hw)` (will save
+the resulting user to the database) in your spec file. Alternatively, if you add
+
+```rb
+config.include FactoryBot::Syntax::Methods
+```
+
+to `RSpec.configure` in __rails_helper.rb__, you can omit the `FactoryBot` and
+just use `build(:user_hw)` / `create(:user_hw)`.
+
+### Finishing up authorization
+
+After you fill in each test, implement enough of the application logic to make
+the test pass. Then go back and write the next test.
+
+Once you finish all your tests and implementation, refactor any obvious bugs,
+flaws, or inefficiencies that remain.
+
+This is the _Red, Green, Refactor_ approach.
+
+### Refactoring tips
+
+You may notice that some tests require you to perform several setup actions
+before you get to the actual test. For example, to log in, you have to visit the
+new session url, fill in the username, fill in the password, and click the "Log
+In" button. To keep your spec file clean and easy-to-read, consider moving
+sequences of actions like this into helper methods in a support module.
+
+Support files typically go in the __spec/support__ directory. Add a __system__
+directory inside __spec/support__ and create a file __auth_system_helper__. Open
+the file and create a `log_in_as` method:
+
+```rb
+module AuthSystemHelper
+  def log_in_as(user)
+    visit new_session_url
+    fill_in "Username", with: user.username
+    fill_in "Password", with: "password"
+    click_button "Log In"
+  end
+end
+```
+
+Now you just need to give your tests in **auth_spec.rb** access to this module.
+You could do this manually by adding
+
+```rb
+require_relative '../support/system/auth_system_helper.rb'
+```
+
+ to the top of __spec/system/auth_spec.rb__. Then inside `RSpec.describe
+ "Auth"`, include the module:
+
+ ```rb
+ include AuthSystemHelper
+ ```
+
+This has the advantage of only loading the files that you need for this
+particular test. There is, however, an alternative way to achieve this result.
+In __rails_helper.rb__, uncomment this line at the end of the first major
+comment block:
+
+```rb
+Dir[Rails.root.join('spec', 'support', '**', '*.rb')].sort.each { |f| require f }
+```
+
+As noted by the comment that precedes this line in the file, this command
+effectively loads **every** __.rb__ file in the entire __support__ directory and
+subdirectories for each test run. In other words, it will not selectively load
+the files needed for your particular test, which could significantly increase
+boot up time if you have many and/or long support files. (You should be okay in
+this case, however.)
+
+There is one more step in this alternative option. Still in __rails_helper.rb__,
+add the following line inside `RSpec.configure`:
+
+```rb
+config.include AuthSystemHelper, type: :system
+```
+
+This will include `AuthSystemHelper` in every system spec file. This approach
+thus has the advantage of making `log_in_as` automatically available to use in
+all the system spec files.
+
+Now that you know how to create helper methods and modules, go ahead and add a
+`sign_up_as(username)` method to your `AuthSystemHelper` as well. Run your tests
+again using these new helper methods to make sure everything is still green!
+
+Now that auth is done, you are ready to move on to [Phase II!](README-ph2-3.md)
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/.gitattributes b/rails/projects/goal_app_refactor/.gitattributes
new file mode 100644
index 0000000..34fb547
--- /dev/null
+++ b/rails/projects/goal_app_refactor/.gitattributes
@@ -0,0 +1,7 @@
+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/.gitignore b/rails/projects/goal_app_refactor/.gitignore
new file mode 100644
index 0000000..4f0da6f
--- /dev/null
+++ b/rails/projects/goal_app_refactor/.gitignore
@@ -0,0 +1,26 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/.rspec b/rails/projects/goal_app_refactor/.rspec
new file mode 100644
index 0000000..f6f85f5
--- /dev/null
+++ b/rails/projects/goal_app_refactor/.rspec
@@ -0,0 +1,3 @@
+--require spec_helper
+--color
+--format documentation
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/.ruby-version b/rails/projects/goal_app_refactor/.ruby-version
new file mode 100644
index 0000000..94ff29c
--- /dev/null
+++ b/rails/projects/goal_app_refactor/.ruby-version
@@ -0,0 +1 @@
+3.1.1
diff --git a/rails/projects/goal_app_refactor/Gemfile b/rails/projects/goal_app_refactor/Gemfile
new file mode 100644
index 0000000..5f397da
--- /dev/null
+++ b/rails/projects/goal_app_refactor/Gemfile
@@ -0,0 +1,56 @@
+source "https://rubygems.org"
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+ruby "3.1.1"
+
+# Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
+gem "rails", "~> 7.0.3"
+
+# The original asset pipeline for Rails [https://github.com/rails/sprockets-rails]
+gem "sprockets-rails"
+
+# Use postgresql as the database for Active Record
+gem "pg", "~> 1.1"
+
+# Use the Puma web server [https://github.com/puma/puma]
+gem "puma", "~> 5.0"
+
+# Use Kredis to get higher-level data types in Redis [https://github.com/rails/kredis]
+# gem "kredis"
+
+# Use Active Model has_secure_password [https://guides.rubyonrails.org/active_model_basics.html#securepassword]
+gem "bcrypt", "~> 3.1.7"
+
+# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
+gem "tzinfo-data", platforms: %i[ mingw mswin x64_mingw jruby ]
+
+# Use Sass to process CSS
+# gem "sassc-rails"
+
+group :development, :test do
+  # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
+  gem "byebug", platforms: %i[ mri mingw x64_mingw ]
+  gem "rspec-rails"
+  gem "factory_bot_rails"
+  gem "shoulda-matchers"
+end
+
+group :development do
+  # Speed up commands on slow machines / big apps [https://github.com/rails/spring]
+  gem "spring"
+  gem "spring-commands-rspec"
+  gem "guard-rspec"
+  gem "annotate"
+  gem "pry-rails"
+  gem "better_errors"
+  gem "binding_of_caller"
+end
+
+group :test do
+  # Use system testing [https://guides.rubyonrails.org/testing.html#system-testing]
+  gem "capybara"
+  gem "selenium-webdriver"
+  gem "webdrivers"
+  gem "faker"
+  gem "launchy"
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/Gemfile.lock b/rails/projects/goal_app_refactor/Gemfile.lock
new file mode 100644
index 0000000..44b2704
--- /dev/null
+++ b/rails/projects/goal_app_refactor/Gemfile.lock
@@ -0,0 +1,297 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailbox (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (>= 2.7.1)
+      net-imap
+      net-pop
+      net-smtp
+    actionmailer (7.0.3)
+      actionpack (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (~> 2.5, >= 2.5.4)
+      net-imap
+      net-pop
+      net-smtp
+      rails-dom-testing (~> 2.0)
+    actionpack (7.0.3)
+      actionview (= 7.0.3)
+      activesupport (= 7.0.3)
+      rack (~> 2.0, >= 2.2.0)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (7.0.3)
+      actionpack (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.6.0)
+      nokogiri (>= 1.8.5)
+    actionview (7.0.3)
+      activesupport (= 7.0.3)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.3.6)
+    activemodel (7.0.3)
+      activesupport (= 7.0.3)
+    activerecord (7.0.3)
+      activemodel (= 7.0.3)
+      activesupport (= 7.0.3)
+    activestorage (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activesupport (= 7.0.3)
+      marcel (~> 1.0)
+      mini_mime (>= 1.1.0)
+    activesupport (7.0.3)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+    addressable (2.8.0)
+      public_suffix (>= 2.0.2, < 5.0)
+    annotate (3.2.0)
+      activerecord (>= 3.2, < 8.0)
+      rake (>= 10.4, < 14.0)
+    bcrypt (3.1.18)
+    better_errors (2.9.1)
+      coderay (>= 1.0.0)
+      erubi (>= 1.0.0)
+      rack (>= 0.9.0)
+    binding_of_caller (1.0.0)
+      debug_inspector (>= 0.0.1)
+    builder (3.2.4)
+    byebug (11.1.3)
+    capybara (3.37.1)
+      addressable
+      matrix
+      mini_mime (>= 0.1.3)
+      nokogiri (~> 1.8)
+      rack (>= 1.6.0)
+      rack-test (>= 0.6.3)
+      regexp_parser (>= 1.5, < 3.0)
+      xpath (~> 3.2)
+    childprocess (4.1.0)
+    coderay (1.1.3)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    debug_inspector (1.1.0)
+    diff-lcs (1.5.0)
+    digest (3.1.0)
+    erubi (1.10.0)
+    factory_bot (6.2.1)
+      activesupport (>= 5.0.0)
+    factory_bot_rails (6.2.0)
+      factory_bot (~> 6.2.0)
+      railties (>= 5.0.0)
+    faker (2.21.0)
+      i18n (>= 1.8.11, < 2)
+    ffi (1.15.5)
+    formatador (1.1.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    guard (2.18.0)
+      formatador (>= 0.2.4)
+      listen (>= 2.7, < 4.0)
+      lumberjack (>= 1.0.12, < 2.0)
+      nenv (~> 0.1)
+      notiffany (~> 0.0)
+      pry (>= 0.13.0)
+      shellany (~> 0.0)
+      thor (>= 0.18.1)
+    guard-compat (1.2.1)
+    guard-rspec (4.7.3)
+      guard (~> 2.1)
+      guard-compat (~> 1.1)
+      rspec (>= 2.99.0, < 4.0)
+    i18n (1.10.0)
+      concurrent-ruby (~> 1.0)
+    launchy (2.5.0)
+      addressable (~> 2.7)
+    listen (3.7.1)
+      rb-fsevent (~> 0.10, >= 0.10.3)
+      rb-inotify (~> 0.9, >= 0.9.10)
+    loofah (2.18.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    lumberjack (1.2.8)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (1.0.2)
+    matrix (0.4.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    minitest (5.15.0)
+    nenv (0.3.0)
+    net-imap (0.2.3)
+      digest
+      net-protocol
+      strscan
+    net-pop (0.1.1)
+      digest
+      net-protocol
+      timeout
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    notiffany (0.1.3)
+      nenv (~> 0.1)
+      shellany (~> 0.0)
+    pg (1.3.5)
+    pry (0.14.1)
+      coderay (~> 1.1)
+      method_source (~> 1.0)
+    pry-rails (0.3.9)
+      pry (>= 0.10.4)
+    public_suffix (4.0.7)
+    puma (5.6.4)
+      nio4r (~> 2.0)
+    racc (1.6.0)
+    rack (2.2.3.1)
+    rack-test (1.1.0)
+      rack (>= 1.0, < 3)
+    rails (7.0.3)
+      actioncable (= 7.0.3)
+      actionmailbox (= 7.0.3)
+      actionmailer (= 7.0.3)
+      actionpack (= 7.0.3)
+      actiontext (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activemodel (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      bundler (>= 1.15.0)
+      railties (= 7.0.3)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.4.2)
+      loofah (~> 2.3)
+    railties (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      method_source
+      rake (>= 12.2)
+      thor (~> 1.0)
+      zeitwerk (~> 2.5)
+    rake (13.0.6)
+    rb-fsevent (0.11.1)
+    rb-inotify (0.10.1)
+      ffi (~> 1.0)
+    regexp_parser (2.5.0)
+    rexml (3.2.5)
+    rspec (3.11.0)
+      rspec-core (~> 3.11.0)
+      rspec-expectations (~> 3.11.0)
+      rspec-mocks (~> 3.11.0)
+    rspec-core (3.11.0)
+      rspec-support (~> 3.11.0)
+    rspec-expectations (3.11.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.11.0)
+    rspec-mocks (3.11.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.11.0)
+    rspec-rails (5.1.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      railties (>= 5.2)
+      rspec-core (~> 3.10)
+      rspec-expectations (~> 3.10)
+      rspec-mocks (~> 3.10)
+      rspec-support (~> 3.10)
+    rspec-support (3.11.0)
+    rubyzip (2.3.2)
+    selenium-webdriver (4.2.1)
+      childprocess (>= 0.5, < 5.0)
+      rexml (~> 3.2, >= 3.2.5)
+      rubyzip (>= 1.2.2, < 3.0)
+      websocket (~> 1.0)
+    shellany (0.0.1)
+    shoulda-matchers (5.1.0)
+      activesupport (>= 5.2.0)
+    spring (4.0.0)
+    spring-commands-rspec (1.0.4)
+      spring (>= 0.9.1)
+    sprockets (4.0.3)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.4.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      sprockets (>= 3.0.0)
+    strscan (3.0.3)
+    thor (1.2.1)
+    timeout (0.3.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    webdrivers (5.0.0)
+      nokogiri (~> 1.6)
+      rubyzip (>= 1.3.0)
+      selenium-webdriver (~> 4.0)
+    websocket (1.2.9)
+    websocket-driver (0.7.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
+    xpath (3.2.0)
+      nokogiri (~> 1.8)
+    zeitwerk (2.5.4)
+
+PLATFORMS
+  x86_64-darwin-20
+
+DEPENDENCIES
+  annotate
+  bcrypt (~> 3.1.7)
+  better_errors
+  binding_of_caller
+  byebug
+  capybara
+  factory_bot_rails
+  faker
+  guard-rspec
+  launchy
+  pg (~> 1.1)
+  pry-rails
+  puma (~> 5.0)
+  rails (~> 7.0.3)
+  rspec-rails
+  selenium-webdriver
+  shoulda-matchers
+  spring
+  spring-commands-rspec
+  sprockets-rails
+  tzinfo-data
+  webdrivers
+
+RUBY VERSION
+   ruby 3.1.1p18
+
+BUNDLED WITH
+   2.3.14
diff --git a/rails/projects/goal_app_refactor/Guardfile b/rails/projects/goal_app_refactor/Guardfile
new file mode 100644
index 0000000..69154fc
--- /dev/null
+++ b/rails/projects/goal_app_refactor/Guardfile
@@ -0,0 +1,5 @@
+guard :rspec, cmd: 'spring rspec' do
+  watch(%r{^app/}) { 'spec' }
+  watch(%r{^spec/}) { 'spec' }
+  watch('config/routes.rb') { 'spec' }
+end
diff --git a/rails/projects/goal_app_refactor/README.md b/rails/projects/goal_app_refactor/README.md
new file mode 100644
index 0000000..f3d93eb
--- /dev/null
+++ b/rails/projects/goal_app_refactor/README.md
@@ -0,0 +1,81 @@
+# Goal App Refactor
+
+In the Goal App that you created a few days ago, you implemented comments by
+using two different tables, `UserComment` and `GoalComment`. Now that you have
+learned about polymorphism and concerns, you can refactor your comment code to
+DRY it up considerably. The best part about this refactor? The tests that you
+wrote the other day will ensure that you do it correctly!
+
+You can use your code from that assignment or download a solution to the Goal
+App project from the repo accessed through the `Download Project` button at the
+bottom of this page. If you download the Goal App solution, don't forget to
+create your database, run the migrations, seed the database, and load the schema
+into test:
+
+```sh
+rails db:create db:migrate db:seed db:test:load
+```
+
+(You will probably want to load the schema into test every time you migrate.)
+
+Run `bundle exec rspec` to make sure all of your specs start out green!
+
+## Adding a polymorphic association
+
+First, use a polymorphic association so that `User`s and `Goal`s will both refer
+to the same `Comment` model. Think through what you will need to to make this
+happen. Think about which associations you will need. Each `User` and `Goal`
+should have many `comments`, and comments will need to be associated with a
+commenting user and a user or goal being commented on.
+
+Go ahead and create this new model and migration. Remember that you'll need to
+remove the old comment tables when you create the new one. See if you can
+migrate the data from the old tables without losing it. (Remember that you can
+use regular Ruby / Active Record code in your migration files!)
+
+> **Tip:** If you are moving data from your old tables to your new table in the
+> migration, you will probably want to use `up` and `down` methods instead of
+> `change` so you can make the migration reversible. Note that you will need all
+> of the models that you are accessing to be defined in __app/models__ for such
+> a transfer to work.
+
+Run `bundle exec rspec` again. Now you should see lots of red.
+
+Next, write the associations to link all of your classes together
+polymorphically. You'll also need to add a `CommentsController`--use one of the
+project's old comment controllers as a guide--update your routes, and update
+__shared/\_comments_form.html.erb__.
+
+When you finish, run `bundle exec rspec` again. If everything is done correctly,
+you should see all green. Isn't this better than that lousy two-table solution?
+
+## DRYing up your code with concerns
+
+"Now wait just one minute!" you say. "I've removed an unneeded table and made
+my comment model more extensible, but my code still isn't very _DRY_ if I'm
+writing identical code for both `User` comments and `Goal` comments."
+
+Well, funny you should mention that. **Concerns** are a great way to factor out
+your association logic and DRY out your code. Go ahead and create a
+`Commentable` concern to do just that. (Refer back to the "Concerns" reading if
+you need help.)
+
+When the tests stay green you can pat yourself on the back for successfully
+solving a problem using two different strategies. RSpec and Capybara give you
+the comfort and security of knowing that although things have changed beneath
+the hood, the presentation is identical because **the tests are still green**.
+Isn't this a nice feeling?
+
+## Resources
+
+* [Polymorphic associations][poly-reading]
+* [Concerns]
+
+[poly-reading]: https://guides.rubyonrails.org/association_basics.html#polymorphic-associations
+[Concerns]: https://signalvnoise.com/posts/3372-put-chubby-models-on-a-diet-with-concerns
+
+## What you've learned
+
+In this hw, you learned how to DRY out your code using polymorphic associations
+and concerns. Along the way, you also discovered the benefits of having
+established tests that test behavior rather than implementation details.
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/Rakefile b/rails/projects/goal_app_refactor/Rakefile
new file mode 100644
index 0000000..d298243
--- /dev/null
+++ b/rails/projects/goal_app_refactor/Rakefile
@@ -0,0 +1,6 @@
+# Add your own tasks in files placed in lib/tasks ending in .rake,
+# for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
+
+require_relative "config/application"
+
+Rails.application.load_tasks
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/assets/config/manifest.js b/rails/projects/goal_app_refactor/app/assets/config/manifest.js
new file mode 100644
index 0000000..f83f92b
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/assets/config/manifest.js
@@ -0,0 +1,2 @@
+//= link_tree ../images
+//= link_directory ../stylesheets .css
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/assets/images/.keep b/rails/projects/goal_app_refactor/app/assets/images/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/app/assets/stylesheets/application.css b/rails/projects/goal_app_refactor/app/assets/stylesheets/application.css
new file mode 100644
index 0000000..21c9ac5
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/assets/stylesheets/application.css
@@ -0,0 +1,15 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS (and SCSS, if configured) file within this directory, lib/assets/stylesheets, or any plugin's
+ * vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree .
+ *= require_self
+ */
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/controllers/application_controller.rb b/rails/projects/goal_app_refactor/app/controllers/application_controller.rb
new file mode 100644
index 0000000..88c7465
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/controllers/application_controller.rb
@@ -0,0 +1,31 @@
+class ApplicationController < ActionController::Base
+  protect_from_forgery with: :exception
+  helper_method :current_user, :current_user_name, :current_user_id
+
+  def current_user
+    @current_user ||= User.find_by(session_token: session[:session_token])
+  end
+
+  def login!(user)
+    @current_user = user
+    session[:session_token] = user.reset_session_token!
+  end
+
+  def current_user_id
+    current_user ? current_user.id : nil
+  end
+
+  def current_user_name
+    current_user ? current_user.username : nil
+  end
+
+  # Before filters
+
+  def require_current_user!
+    redirect_to new_user_url unless current_user
+  end
+
+  def require_no_current_user!
+    redirect_to root_url if current_user
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/controllers/cheers_controller.rb b/rails/projects/goal_app_refactor/app/controllers/cheers_controller.rb
new file mode 100644
index 0000000..fddb506
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/controllers/cheers_controller.rb
@@ -0,0 +1,35 @@
+class CheersController < ApplicationController
+  before_action :require_current_user!
+
+  def index
+    @cheers = current_user.cheers_received
+  end
+
+  def create
+    if current_user.cheer_count <= 0
+      redirect_back fallback_location: users_url
+      return
+    end
+
+    @cheer = Cheer.new(
+      giver_id: current_user.id,
+      goal_id: params[:goal_id]
+    )
+    if @cheer.save
+      current_user.decrement_cheer_count!
+      raise 'went over cheer limit' if current_user.cheer_count < 0
+      goal_owner_name = Goal.find(params[:goal_id]).author.username
+      flash[:notices] = ["You cheered #{goal_owner_name}'s goal!"]
+    else
+      flash[:errors] = @cheer.errors.full_messages
+    end
+
+    redirect_back fallback_location: users_url
+  end
+
+  private
+
+  def cheer_params
+    params.require(:cheer).permit(:giver_id, :goal_id)
+  end
+end
diff --git a/rails/projects/goal_app_refactor/app/controllers/concerns/.keep b/rails/projects/goal_app_refactor/app/controllers/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/app/controllers/goal_comments_controller.rb b/rails/projects/goal_app_refactor/app/controllers/goal_comments_controller.rb
new file mode 100644
index 0000000..d2f6d10
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/controllers/goal_comments_controller.rb
@@ -0,0 +1,21 @@
+class GoalCommentsController < ApplicationController
+  def create
+    @comment = GoalComment.new(comment_params)
+    @comment.author_id = current_user.id
+
+    if @comment.save
+      flash[:notices] = ['Comment saved!']
+    else
+      flash[:errors] = @comment.errors.full_messages
+    end
+
+    redirect_back fallback_location: users_url
+  end
+
+  private
+
+  def comment_params
+    params.require(:comment).permit(:goal_id, :body)
+  end
+
+end
diff --git a/rails/projects/goal_app_refactor/app/controllers/goals_controller.rb b/rails/projects/goal_app_refactor/app/controllers/goals_controller.rb
new file mode 100644
index 0000000..6764ea0
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/controllers/goals_controller.rb
@@ -0,0 +1,60 @@
+class GoalsController < ApplicationController
+  before_action :require_current_user!
+  before_action :set_goal, only: %i[show edit update destroy]
+
+  def index
+    @goals = current_user.goals
+  end
+
+  def show
+  end
+
+  def new
+    @goal = Goal.new
+  end
+
+  def create
+    @goal = current_user.goals.new(goal_params)
+
+    if @goal.save
+      flash[:notices] = ['Goal saved!']
+      redirect_to goal_url(@goal)
+    else
+      flash.now[:errors] = @goal.errors.full_messages
+      render :new
+    end
+  end
+
+  def edit
+  end
+
+  def update
+    if @goal.update(goal_params)
+      flash[:notices] = ['Goal updated!']
+      if !request.referer || request.referer == edit_goal_url(@goal)
+        redirect_to @goal
+      else
+        redirect_to request.referer
+      end
+    else
+      flash[:errors] = @goal.errors.full_messages
+      render :edit
+    end
+  end
+
+  def destroy
+    @goal.destroy
+    flash[:notices] = ['Goal deleted!']
+    redirect_to goals_url
+  end
+
+  private
+
+  def set_goal
+    @goal = Goal.find(params[:id])
+  end
+
+  def goal_params
+    params.require(:goal).permit(:title, :details, :private, :completed)
+  end
+end
diff --git a/rails/projects/goal_app_refactor/app/controllers/sessions_controller.rb b/rails/projects/goal_app_refactor/app/controllers/sessions_controller.rb
new file mode 100644
index 0000000..2933dda
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/controllers/sessions_controller.rb
@@ -0,0 +1,33 @@
+class SessionsController < ApplicationController
+  before_action :require_current_user!, only: [:destroy]
+  before_action :require_no_current_user!, only: [:new, :create]
+
+  def new
+    @user = User.new
+  end
+
+  def create
+    credentials = [user_params[:username], user_params[:password]]
+    @user = User.find_by_credentials(*credentials)
+    if @user
+      login!(@user)
+      redirect_to user_url(@user)
+    else
+      @user = User.new(username: credentials[0])
+      flash.now[:errors] = ['Invalid credentials.']
+      render :new
+    end
+  end
+
+  def destroy
+    current_user.reset_session_token!
+    session[:session_token] = nil
+    redirect_to new_session_url
+  end
+
+  private
+
+  def user_params
+    params.require(:user).permit(:username, :password)
+  end
+end
diff --git a/rails/projects/goal_app_refactor/app/controllers/user_comments_controller.rb b/rails/projects/goal_app_refactor/app/controllers/user_comments_controller.rb
new file mode 100644
index 0000000..94833e0
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/controllers/user_comments_controller.rb
@@ -0,0 +1,21 @@
+class UserCommentsController < ApplicationController
+  def create
+    @comment = UserComment.new(user_comment_params)
+    @comment.author_id = current_user.id
+
+    if @comment.save
+      flash[:notices] = ['Comment saved!']
+    else
+      flash[:errors] = @comment.errors.full_messages
+    end
+
+    redirect_back fallback_location: users_url
+  end
+
+  private
+
+  def user_comment_params
+    params.require(:comment).permit(:recipient_id, :body)
+  end
+
+end
diff --git a/rails/projects/goal_app_refactor/app/controllers/users_controller.rb b/rails/projects/goal_app_refactor/app/controllers/users_controller.rb
new file mode 100644
index 0000000..531d2c8
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/controllers/users_controller.rb
@@ -0,0 +1,32 @@
+class UsersController < ApplicationController
+  before_action :require_no_current_user!, only: %i[new create]
+
+  def index
+    @users = User.all
+  end
+
+  def show
+    @user = User.find(params[:id])
+  end
+
+  def new
+    @user = User.new
+  end
+
+  def create
+    @user = User.new(user_params)
+    if @user.save
+      login!(@user)
+      redirect_to user_url(@user)
+    else
+      flash.now[:errors] = @user.errors.full_messages
+      render :new
+    end
+  end
+
+  private
+
+  def user_params
+    params.require(:user).permit(:username, :password)
+  end
+end
diff --git a/rails/projects/goal_app_refactor/app/models/application_record.rb b/rails/projects/goal_app_refactor/app/models/application_record.rb
new file mode 100644
index 0000000..b63caeb
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/models/application_record.rb
@@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+  primary_abstract_class
+end
diff --git a/rails/projects/goal_app_refactor/app/models/cheer.rb b/rails/projects/goal_app_refactor/app/models/cheer.rb
new file mode 100644
index 0000000..f22dc5f
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/models/cheer.rb
@@ -0,0 +1,22 @@
+# == Schema Information
+#
+# Table name: cheers
+#
+#  id         :bigint           not null, primary key
+#  giver_id   :bigint           not null
+#  goal_id    :bigint           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+class Cheer < ApplicationRecord
+  CHEER_LIMIT = 12
+  ##
+  # Don't let others change the limit!
+  ##
+  CHEER_LIMIT.freeze
+
+  validates :goal_id, uniqueness: { scope: :giver_id }
+  
+  belongs_to :giver, class_name: :User
+  belongs_to :goal
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/models/concerns/.keep b/rails/projects/goal_app_refactor/app/models/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/app/models/goal.rb b/rails/projects/goal_app_refactor/app/models/goal.rb
new file mode 100644
index 0000000..4a691f1
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/models/goal.rb
@@ -0,0 +1,24 @@
+# == Schema Information
+#
+# Table name: goals
+#
+#  id         :bigint           not null, primary key
+#  title      :string           not null
+#  private    :boolean          default(FALSE), not null
+#  details    :text
+#  completed  :boolean          default(FALSE), not null
+#  author_id  :bigint           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+class Goal < ApplicationRecord
+  validates :title, presence: true
+
+  belongs_to :author, class_name: :User
+  has_many :comments, class_name: :GoalComment, dependent: :destroy
+  has_many :cheers, dependent: :destroy
+
+  def cheered_by?(user)
+    cheers.exists?(giver_id: user.id)
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/models/goal_comment.rb b/rails/projects/goal_app_refactor/app/models/goal_comment.rb
new file mode 100644
index 0000000..506adfa
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/models/goal_comment.rb
@@ -0,0 +1,17 @@
+# == Schema Information
+#
+# Table name: goal_comments
+#
+#  id         :bigint           not null, primary key
+#  body       :string           not null
+#  author_id  :bigint           not null
+#  goal_id    :bigint           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+class GoalComment < ApplicationRecord
+  validates :body, presence: true
+
+  belongs_to :author, class_name: :User
+  belongs_to :goal
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/models/user.rb b/rails/projects/goal_app_refactor/app/models/user.rb
new file mode 100644
index 0000000..f457819
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/models/user.rb
@@ -0,0 +1,96 @@
+# == Schema Information
+#
+# Table name: users
+#
+#  id              :bigint           not null, primary key
+#  username        :string           not null
+#  session_token   :string           not null
+#  password_digest :string           not null
+#  created_at      :datetime         not null
+#  updated_at      :datetime         not null
+#  cheer_count     :integer          not null
+#
+class User < ApplicationRecord
+  validates :session_token, presence: true
+  validates :username, uniqueness: true, presence: true
+  validates :password, length: { minimum: 6, allow_nil: true }
+  validates :password_digest, presence: { message: 'Password can\'t be blank.' }
+  validates :cheer_count, numericality: { only_integer: true, greater_than_or_equal_to: 0 }
+  
+  attr_reader :password
+
+  before_validation :ensure_session_token, :ensure_cheer_count
+
+  has_many :goals, 
+    foreign_key: :author_id,
+    dependent: :destroy,
+    inverse_of: :author
+
+  has_many :comments,
+    foreign_key: :recipient_id,
+    class_name: :UserComment,
+    dependent: :destroy,
+    inverse_of: :recipient
+
+  has_many :authored_comments, 
+    foreign_key: :author_id,
+    class_name: :UserComment,
+    dependent: :destroy,
+    inverse_of: :author
+
+  has_many :cheers_given,
+    class_name: :Cheer,
+    foreign_key: :giver_id,
+    dependent: :destroy,
+    inverse_of: :giver
+
+  has_many :cheers_received,
+    through: :goals,
+    source: :cheers
+
+  def self.find_by_credentials(username, password)
+    user = User.find_by(username: username)
+    # `user&.is_password?(password)` is syntactic sugar for
+    # `user && user.is_password?(password)`
+    user&.is_password?(password) ? user : nil
+  end
+
+  def reset_session_token!
+    self.session_token = generate_unique_session_token
+    self.save!
+    self.session_token
+  end
+
+  def is_password?(maybe_password)
+    BCrypt::Password.new(self.password_digest).is_password?(maybe_password)
+  end
+
+  def password=(new_pw)
+    @password = new_pw
+    self.password_digest = BCrypt::Password.create(new_pw)
+  end
+
+  def decrement_cheer_count!
+    self.cheer_count -= 1
+    self.save!
+  end
+
+  private
+
+  def generate_unique_session_token
+    # `SecureRandom::urlsafe_base64` does not guarantee uniqueness. Wrapping
+    # this call in a loop ensures that no other user has the generated token.
+    loop do
+      session_token = SecureRandom::urlsafe_base64(16)
+      return session_token unless User.exists?(session_token: session_token)
+    end
+  end
+
+  def ensure_session_token
+    self.session_token ||= generate_unique_session_token
+  end
+
+  def ensure_cheer_count
+    self.cheer_count ||= Cheer::CHEER_LIMIT
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/models/user_comment.rb b/rails/projects/goal_app_refactor/app/models/user_comment.rb
new file mode 100644
index 0000000..f893b8d
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/models/user_comment.rb
@@ -0,0 +1,17 @@
+# == Schema Information
+#
+# Table name: user_comments
+#
+#  id           :bigint           not null, primary key
+#  body         :string           not null
+#  author_id    :bigint           not null
+#  recipient_id :bigint           not null
+#  created_at   :datetime         not null
+#  updated_at   :datetime         not null
+#
+class UserComment < ApplicationRecord
+  validates :body, presence: true
+
+  belongs_to :author, class_name: :User
+  belongs_to :recipient, class_name: :User
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/views/cheers/index.html.erb b/rails/projects/goal_app_refactor/app/views/cheers/index.html.erb
new file mode 100644
index 0000000..4fc4c13
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/cheers/index.html.erb
@@ -0,0 +1,19 @@
+<h1>My Cheers</h1>
+
+<% @cheers.each do |cheer| %>
+  <table class="cheer">
+    <tr>
+      <th>Cheer given by:</th>
+    </tr>
+    <tr>
+      <td><%= cheer.giver.username %></td>
+    </tr>
+    <tr>
+      <th>For goal of:</th>
+    </tr>
+    <tr>
+      <td><%= cheer.goal.title %></td>
+    </tr>
+  </table>
+  <br />
+<% end %>
diff --git a/rails/projects/goal_app_refactor/app/views/goals/_goal_form.html.erb b/rails/projects/goal_app_refactor/app/views/goals/_goal_form.html.erb
new file mode 100644
index 0000000..7ab9c7d
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/goals/_goal_form.html.erb
@@ -0,0 +1,35 @@
+<% action = (action_type == :new) ? goals_url : goal_url(goal) %>
+<% button_text = (action_type == :new) ? "New Goal" : "Update Goal"%>
+
+<%= render 'shared/errors' %>
+
+<form action="<%= action %>" method="POST">
+  <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>">
+  <% if action_type == :edit %>
+    <input type="hidden" name="_method" value="PUT">
+  <% end %>
+
+  <label>Title:
+    <input type="text" value="<%= goal.title %>" name="goal[title]">
+  </label>
+  <br>
+
+  <label>Details:
+    <textarea name="goal[details]"><%= goal.details %></textarea>
+  </label>
+  <br>
+
+  <label>Private?
+    <input type="checkbox" name="goal[private]"
+      <%= 'checked="true"' if goal.private %>>
+  </label>
+  <br>
+
+  <label>Completed?
+    <input type="checkbox" name="goal[completed]"
+      <%= 'checked="true"' if goal.private %>>
+  </label>
+  <br>
+
+  <input type="submit" value="<%= button_text %>">
+</form>
diff --git a/rails/projects/goal_app_refactor/app/views/goals/edit.html.erb b/rails/projects/goal_app_refactor/app/views/goals/edit.html.erb
new file mode 100644
index 0000000..e12fa6f
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/goals/edit.html.erb
@@ -0,0 +1,3 @@
+<h2>Edit Goal</h2>
+
+<%= render "goal_form", action_type: :edit, goal: @goal %>
diff --git a/rails/projects/goal_app_refactor/app/views/goals/index.html.erb b/rails/projects/goal_app_refactor/app/views/goals/index.html.erb
new file mode 100644
index 0000000..ef04e31
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/goals/index.html.erb
@@ -0,0 +1,6 @@
+<h1>Your Goals</h1>
+<ul>
+  <% @goals.each do |goal| %>
+    <%= render "shared/show_goal_basics", goal: goal %>
+  <% end %>
+</ul>
diff --git a/rails/projects/goal_app_refactor/app/views/goals/new.html.erb b/rails/projects/goal_app_refactor/app/views/goals/new.html.erb
new file mode 100644
index 0000000..bc42293
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/goals/new.html.erb
@@ -0,0 +1,2 @@
+<h2>New Goal</h2>
+<%= render "goal_form", action_type: :new, goal: @goal %>
diff --git a/rails/projects/goal_app_refactor/app/views/goals/show.html.erb b/rails/projects/goal_app_refactor/app/views/goals/show.html.erb
new file mode 100644
index 0000000..752d78b
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/goals/show.html.erb
@@ -0,0 +1,56 @@
+<div class="goal">
+
+  <h2>Goal:</h2>
+
+  <table>
+    <tr>
+      <th>Title:</th>
+      <td><%= @goal.title %></td>
+    </tr>
+    <tr>
+      <th>Details:</th>
+      <td><%= @goal.details %></td>
+    </tr>
+    <tr>
+      <th>Visibility:</th>
+      <td>
+        <% if @goal.private %>
+          Private
+        <% else %>
+          Public
+        <% end %>
+      </td>
+    </tr>
+    <tr>
+      <th>Finished?:</th>
+      <td>
+        <% if @goal.completed %>
+          Completed
+        <% else %>
+          Ongoing
+        <% end %>
+      </td>
+    </tr>
+    <tr>
+      <th>Cheers:</th>
+      <td><%= @goal.cheers.length %></td>
+    </tr>
+    <% if current_user && current_user.id == @goal.author_id %>
+      <tr>
+        <th>Completed?</th>
+        <td>
+          <%= render "shared/goal_complete_button", goal: @goal %>
+        </td>
+      </tr>
+    <% end %>
+  </table>
+
+  <div class="goal-comments">
+    <h4>Comments</h4>
+    <% @goal.comments.each do |comment| %>
+      <p><%= comment.body %></p>
+    <% end %>
+  </div>
+  <%= render "shared/comments_form", receiver_id: @goal.id, comment_type: "Goal" %>
+  <!-- add link to author's profile page later -->
+</div>
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/views/layouts/application.html.erb b/rails/projects/goal_app_refactor/app/views/layouts/application.html.erb
new file mode 100644
index 0000000..d24979c
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/layouts/application.html.erb
@@ -0,0 +1,49 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>Goal App</title>
+    <meta name="viewport" content="width=device-width,initial-scale=1">
+    <%= csrf_meta_tags %>
+    <%= csp_meta_tag %>
+
+    <%= stylesheet_link_tag "application" %>
+  </head>
+  <body>
+    <header>
+      <h1>GOAL APP</h1>
+      <%= render "shared/errors" %>
+      <% if flash[:notices] %>
+        <div class="notices">
+          <% flash[:notices].each do |msg| %>
+            <p><b><%= msg %></b></p>
+          <% end %>
+        </div>
+      <% end %>
+
+      <div class="pull-right">
+        <% if current_user %>
+          <p>Welcome <%= current_user_name %></p>
+          <form action="<%= session_url %>" method="post">
+            <input
+              type="hidden"
+              name="authenticity_token"
+              value="<%= form_authenticity_token %>">
+            <input type="hidden" name="_method" value="delete">
+            <input type="submit" value="Log Out">
+          </form>
+
+          <p>Cheers Remaining:
+            <span id="cheer-limit"><%= current_user.cheer_count %></span>
+          </p>
+        <% else %>
+          <p><a href="<%= new_user_url %>">Sign Up</a></p>
+          <p>or</p>
+          <p><a href="<%= new_session_url %>">Log In</a></p>
+        <% end %>
+      </div>
+    </header>
+
+    <%= yield %>
+
+  </body>
+</html>
diff --git a/rails/projects/goal_app_refactor/app/views/sessions/new.html.erb b/rails/projects/goal_app_refactor/app/views/sessions/new.html.erb
new file mode 100644
index 0000000..d141283
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/sessions/new.html.erb
@@ -0,0 +1,3 @@
+<h2>Sign In!</h2>
+
+<%= render "shared/user_form", user: @user, type: :login %>
diff --git a/rails/projects/goal_app_refactor/app/views/shared/_cheer_button.html.erb b/rails/projects/goal_app_refactor/app/views/shared/_cheer_button.html.erb
new file mode 100644
index 0000000..6eba21f
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/shared/_cheer_button.html.erb
@@ -0,0 +1,5 @@
+<form action="<%= goal_cheers_url(goal) %>" method="POST">
+  <input type="hidden" name="authenticity_token" 
+    value="<%= form_authenticity_token %>">
+  <input type="submit" value="Cheer!">
+</form>
diff --git a/rails/projects/goal_app_refactor/app/views/shared/_comments_form.html.erb b/rails/projects/goal_app_refactor/app/views/shared/_comments_form.html.erb
new file mode 100644
index 0000000..021a351
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/shared/_comments_form.html.erb
@@ -0,0 +1,16 @@
+<% if current_user %>
+  <h3>New Comment</h3>
+
+  <%= render 'shared/errors' %>
+  <% receiver = comment_type == "User" ? :recipient_id : :goal_id %>
+  <% url =  comment_type == "User" ? user_comments_url : goal_comments_url %>
+
+  <form action="<%= url %>" method="POST">
+    <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>">
+    <input type="hidden" name=<%= "comment[#{receiver}]" %> value="<%= receiver_id %>">
+    <label>Comment
+      <textarea name="comment[body]"></textarea>
+    </label>
+    <input type="submit" value="Save Comment">
+  </form>
+<% end %>
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/app/views/shared/_errors.html.erb b/rails/projects/goal_app_refactor/app/views/shared/_errors.html.erb
new file mode 100644
index 0000000..f2babc0
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/shared/_errors.html.erb
@@ -0,0 +1,7 @@
+<% if flash[:errors] %>
+  <div class="errors">
+    <% flash[:errors].each do |msg| %>
+      <p><b><%= msg %></b></p>
+    <% end %>
+  </div>
+<% end %>
diff --git a/rails/projects/goal_app_refactor/app/views/shared/_goal_complete_button.html.erb b/rails/projects/goal_app_refactor/app/views/shared/_goal_complete_button.html.erb
new file mode 100644
index 0000000..8c2a6ea
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/shared/_goal_complete_button.html.erb
@@ -0,0 +1,9 @@
+<form action="<%= goal_url(goal) %>" method="POST">
+  <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>">
+  <input type="hidden" name="_method" value="PUT">
+  <input type="hidden" name="goal[completed]" value="<%= !goal.completed %>">
+  <input type="submit" 
+    value="<%= goal.completed ? 'Oops! Not yet complete.' : 'Complete' %>"
+    id="goal_<%= goal.id %>_completed"
+  >
+</form>
diff --git a/rails/projects/goal_app_refactor/app/views/shared/_show_goal_basics.html.erb b/rails/projects/goal_app_refactor/app/views/shared/_show_goal_basics.html.erb
new file mode 100644
index 0000000..7d2fc26
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/shared/_show_goal_basics.html.erb
@@ -0,0 +1,24 @@
+<% privacy = (goal.private) ? "private" : "public" %>
+<% completedness = (goal.completed) ? "Complete" : "Ongoing"%>
+
+<li>
+  <a href="<%= goal_url(goal) %>"><%= goal.title %></a>
+  <p><i><%= privacy %></i></p>
+  <p><i><%= completedness %></i></p>
+  <br>
+
+  <% if current_user && current_user.id == goal.author_id %>
+    <%= render "shared/goal_complete_button", goal: goal %>
+    <br>
+    <form action="<%= goal_url(goal) %>" method="post">
+        <input
+          type="hidden"
+          name="authenticity_token"
+          value="<%= form_authenticity_token %>">
+        <input type="hidden" name="_method" value="delete">
+        <input type="submit" value="<%= "delete '#{goal.title}' goal" %>">
+      </form>
+  <% elsif current_user && !(goal.cheered_by?(current_user)) && current_user.cheer_count > 0 %>
+    <%= render "shared/cheer_button", goal: goal %>
+  <% end %>
+</li>
diff --git a/rails/projects/goal_app_refactor/app/views/shared/_user_form.html.erb b/rails/projects/goal_app_refactor/app/views/shared/_user_form.html.erb
new file mode 100644
index 0000000..060c6d3
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/shared/_user_form.html.erb
@@ -0,0 +1,17 @@
+<% action = (type == :newuser) ? users_url : session_url %>
+<% button_text = (type == :newuser) ? "Sign Up" : "Log In" %>
+
+<form action="<%= action %>" method="POST">
+  <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>">
+  <label>Username:
+    <input type="text" value="<%= @user.username %>" name="user[username]">
+  </label>
+  <br>
+
+  <label>Password:
+    <input type="password" value="<%= @user.password %>" name="user[password]">
+  </label>
+  <br>
+
+  <input type="submit" value="<%= button_text %>">
+</form>
diff --git a/rails/projects/goal_app_refactor/app/views/users/index.html.erb b/rails/projects/goal_app_refactor/app/views/users/index.html.erb
new file mode 100644
index 0000000..889d29f
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/users/index.html.erb
@@ -0,0 +1,5 @@
+<h2>Users</h2>
+
+<% @users.each do |user| %>
+  <a href="<%= user_url(user) %>"><%= user.username %></a>
+<% end %>
diff --git a/rails/projects/goal_app_refactor/app/views/users/new.html.erb b/rails/projects/goal_app_refactor/app/views/users/new.html.erb
new file mode 100644
index 0000000..6df27f1
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/users/new.html.erb
@@ -0,0 +1,3 @@
+<h2>Sign Up!</h2>
+
+<%= render "shared/user_form", user: @user, type: :newuser %>
diff --git a/rails/projects/goal_app_refactor/app/views/users/show.html.erb b/rails/projects/goal_app_refactor/app/views/users/show.html.erb
new file mode 100644
index 0000000..bd021f2
--- /dev/null
+++ b/rails/projects/goal_app_refactor/app/views/users/show.html.erb
@@ -0,0 +1,32 @@
+<div class="profile">
+  <h2><%= @user.username.capitalize %>'s Profile</h2>
+
+  <div class="profile-section">
+    <% @user.comments.each do |comment| %>
+      <p><%= comment.body %></p>
+    <% end %>
+
+    <%= render "shared/comments_form", receiver_id: @user.id, comment_type: "User" %>
+  </div>
+
+  <div class="profile-section">
+    <h3><%= @user.username.capitalize %>'s Goals:</h3>
+
+    <% if @user == current_user %>
+      <a href="<%= new_goal_url %>">New Goal</a>
+      <a href="<%= cheers_url %>">My Cheers!</a>
+    <% end %>
+
+    <ul>
+      <% @user.goals.each do |goal| %>
+        <% if (current_user && current_user.id == @user.id) || !(goal.private) %>
+          <%= render "shared/show_goal_basics", goal: goal %>
+        <% end %>
+      <% end %>
+    </ul>
+  </div>
+</div>
+
+<div class="all-users">
+  <a href="<%= users_url %>">All Users</a>
+</div>
diff --git a/rails/projects/goal_app_refactor/bin/bundle b/rails/projects/goal_app_refactor/bin/bundle
new file mode 100644
index 0000000..2060668
--- /dev/null
+++ b/rails/projects/goal_app_refactor/bin/bundle
@@ -0,0 +1,114 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'bundle' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "rubygems"
+
+m = Module.new do
+  module_function
+
+  def invoked_as_script?
+    File.expand_path($0) == File.expand_path(__FILE__)
+  end
+
+  def env_var_version
+    ENV["BUNDLER_VERSION"]
+  end
+
+  def cli_arg_version
+    return unless invoked_as_script? # don't want to hijack other binstubs
+    return unless "update".start_with?(ARGV.first || " ") # must be running `bundle update`
+    bundler_version = nil
+    update_index = nil
+    ARGV.each_with_index do |a, i|
+      if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
+        bundler_version = a
+      end
+      next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
+      bundler_version = $1
+      update_index = i
+    end
+    bundler_version
+  end
+
+  def gemfile
+    gemfile = ENV["BUNDLE_GEMFILE"]
+    return gemfile if gemfile && !gemfile.empty?
+
+    File.expand_path("../Gemfile", __dir__)
+  end
+
+  def lockfile
+    lockfile =
+      case File.basename(gemfile)
+      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
+      else "#{gemfile}.lock"
+      end
+    File.expand_path(lockfile)
+  end
+
+  def lockfile_version
+    return unless File.file?(lockfile)
+    lockfile_contents = File.read(lockfile)
+    return unless lockfile_contents =~ /\n\nBUNDLED WITH\n\s{2,}(#{Gem::Version::VERSION_PATTERN})\n/
+    Regexp.last_match(1)
+  end
+
+  def bundler_requirement
+    @bundler_requirement ||=
+      env_var_version || cli_arg_version ||
+        bundler_requirement_for(lockfile_version)
+  end
+
+  def bundler_requirement_for(version)
+    return "#{Gem::Requirement.default}.a" unless version
+
+    bundler_gem_version = Gem::Version.new(version)
+
+    requirement = bundler_gem_version.approximate_recommendation
+
+    return requirement unless Gem.rubygems_version < Gem::Version.new("2.7.0")
+
+    requirement += ".a" if bundler_gem_version.prerelease?
+
+    requirement
+  end
+
+  def load_bundler!
+    ENV["BUNDLE_GEMFILE"] ||= gemfile
+
+    activate_bundler
+  end
+
+  def activate_bundler
+    gem_error = activation_error_handling do
+      gem "bundler", bundler_requirement
+    end
+    return if gem_error.nil?
+    require_error = activation_error_handling do
+      require "bundler/version"
+    end
+    return if require_error.nil? && Gem::Requirement.new(bundler_requirement).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+    warn "Activating bundler (#{bundler_requirement}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_requirement}'`"
+    exit 42
+  end
+
+  def activation_error_handling
+    yield
+    nil
+  rescue StandardError, LoadError => e
+    e
+  end
+end
+
+m.load_bundler!
+
+if m.invoked_as_script?
+  load Gem.bin_path("bundler", "bundle")
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/bin/rails b/rails/projects/goal_app_refactor/bin/rails
new file mode 100644
index 0000000..f4b7505
--- /dev/null
+++ b/rails/projects/goal_app_refactor/bin/rails
@@ -0,0 +1,5 @@
+#!/usr/bin/env ruby
+load File.expand_path("spring", __dir__)
+APP_PATH = File.expand_path("../config/application", __dir__)
+require_relative "../config/boot"
+require "rails/commands"
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/bin/rake b/rails/projects/goal_app_refactor/bin/rake
new file mode 100644
index 0000000..265863c
--- /dev/null
+++ b/rails/projects/goal_app_refactor/bin/rake
@@ -0,0 +1,5 @@
+#!/usr/bin/env ruby
+load File.expand_path("spring", __dir__)
+require_relative "../config/boot"
+require "rake"
+Rake.application.run
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/bin/rspec b/rails/projects/goal_app_refactor/bin/rspec
new file mode 100644
index 0000000..0e6bf85
--- /dev/null
+++ b/rails/projects/goal_app_refactor/bin/rspec
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+load File.expand_path("spring", __dir__)
+require 'bundler/setup'
+load Gem.bin_path('rspec-core', 'rspec')
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/bin/setup b/rails/projects/goal_app_refactor/bin/setup
new file mode 100644
index 0000000..9bd670f
--- /dev/null
+++ b/rails/projects/goal_app_refactor/bin/setup
@@ -0,0 +1,33 @@
+#!/usr/bin/env ruby
+require "fileutils"
+
+# path to your application root.
+APP_ROOT = File.expand_path("..", __dir__)
+
+def system!(*args)
+  system(*args) || abort("\n== Command #{args} failed ==")
+end
+
+FileUtils.chdir APP_ROOT do
+  # This script is a way to set up or update your development environment automatically.
+  # This script is idempotent, so that you can run it at any time and get an expectable outcome.
+  # Add necessary setup steps to this file.
+
+  puts "== Installing dependencies =="
+  system! "gem install bundler --conservative"
+  system("bundle check") || system!("bundle install")
+
+  # puts "\n== Copying sample files =="
+  # unless File.exist?("config/database.yml")
+  #   FileUtils.cp "config/database.yml.sample", "config/database.yml"
+  # end
+
+  puts "\n== Preparing database =="
+  system! "bin/rails db:prepare"
+
+  puts "\n== Removing old logs and tempfiles =="
+  system! "bin/rails log:clear tmp:clear"
+
+  puts "\n== Restarting application server =="
+  system! "bin/rails restart"
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/bin/spring b/rails/projects/goal_app_refactor/bin/spring
new file mode 100644
index 0000000..dd65a0d
--- /dev/null
+++ b/rails/projects/goal_app_refactor/bin/spring
@@ -0,0 +1,14 @@
+#!/usr/bin/env ruby
+
+# This file loads Spring without using loading other gems in the Gemfile, in order to be fast.
+# It gets overwritten when you run the `spring binstub` command.
+
+if !defined?(Spring) && [nil, "development", "test"].include?(ENV["RAILS_ENV"])
+  require "bundler"
+
+  Bundler.locked_gems.specs.find { |spec| spec.name == "spring" }&.tap do |spring|
+    Gem.use_paths Gem.dir, Bundler.bundle_path.to_s, *Gem.path
+    gem "spring", spring.version
+    require "spring/binstub"
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config.ru b/rails/projects/goal_app_refactor/config.ru
new file mode 100644
index 0000000..38cc27a
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config.ru
@@ -0,0 +1,6 @@
+# This file is used by Rack-based servers to start the application.
+
+require_relative "config/environment"
+
+run Rails.application
+Rails.application.load_server
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/application.rb b/rails/projects/goal_app_refactor/config/application.rb
new file mode 100644
index 0000000..2f23d7c
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/application.rb
@@ -0,0 +1,35 @@
+require_relative "boot"
+
+require "rails"
+# Pick the frameworks you want:
+require "active_model/railtie"
+# require "active_job/railtie"
+require "active_record/railtie"
+# require "active_storage/engine"
+require "action_controller/railtie"
+# require "action_mailer/railtie"
+# require "action_mailbox/engine"
+# require "action_text/engine"
+require "action_view/railtie"
+# require "action_cable/engine"
+require "rails/test_unit/railtie"
+
+# Require the gems listed in Gemfile, including any gems
+# you've limited to :test, :development, or :production.
+Bundler.require(*Rails.groups)
+
+module GoalAppRefactor
+  class Application < Rails::Application
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults 7.0
+
+    # Configuration for the application, engines, and railties goes here.
+    #
+    # These settings can be overridden in specific environments using the files
+    # in config/environments, which are processed later.
+    #
+    # config.time_zone = "Central Time (US & Canada)"
+    # config.eager_load_paths << Rails.root.join("extras")
+    config.generators.test_framework = nil
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/boot.rb b/rails/projects/goal_app_refactor/config/boot.rb
new file mode 100644
index 0000000..2820116
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/boot.rb
@@ -0,0 +1,3 @@
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+
+require "bundler/setup" # Set up gems listed in the Gemfile.
diff --git a/rails/projects/goal_app_refactor/config/credentials.yml.enc b/rails/projects/goal_app_refactor/config/credentials.yml.enc
new file mode 100644
index 0000000..51d2bae
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/credentials.yml.enc
@@ -0,0 +1 @@
+21uJLfPs209U8WqdyM+EgxUXzTyRtGPhEPVegHynOi7TUpMBttxqrct+3j8qPJtCxIuEmj0ZINs7DQjW7+2W+zOzMhgGYM3UkQRZOAUrC/cowUY1CncTUXp8QJQoSlZdI/0w7KPn21a8VXmdP/tRukNpHt9rvegw1YWWocXwC+wBDbDEwo8NzZ/olfnJe7kmlPeEVF2Uwpto2CSAitTmMVNO2CALXHqFCLpD58bMmBsLbde5FiL5NqWRsTPqIztIZSsUPldMd91Ga+UWp8Y53UTFEPqXfkc3ByzbiMDfnEUelH/TUaP0lXMHW2s0uqbzrGYRYR11GbkNZzC6mq0TYWP9ZcD7C6BYsckseYpFtfRG/S/ObZGl9i3q7eH0nw9elhBlAR/iuEGqEFhUCnQb8TCXMl0WOixAmKym--tmCOmA66YH47qaqi--2Cr++knYbT7uOx23m+pstg==
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/database.yml b/rails/projects/goal_app_refactor/config/database.yml
new file mode 100644
index 0000000..22bb961
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/database.yml
@@ -0,0 +1,86 @@
+# PostgreSQL. Versions 9.3 and up are supported.
+#
+# Install the pg driver:
+#   gem install pg
+# On macOS with Homebrew:
+#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
+# On macOS with MacPorts:
+#   gem install pg -- --with-pg-config=/opt/local/lib/postgresql84/bin/pg_config
+# On Windows:
+#   gem install pg
+#       Choose the win32 build.
+#       Install PostgreSQL and put its /bin directory on your path.
+#
+# Configure Using Gemfile
+# gem "pg"
+#
+default: &default
+  adapter: postgresql
+  encoding: unicode
+  # For details on connection pooling, see Rails configuration guide
+  # https://guides.rubyonrails.org/configuring.html#database-pooling
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+
+development:
+  <<: *default
+  database: goal_app_refactor_development
+
+  # The specified database role being used to connect to postgres.
+  # To create additional roles in postgres see `$ createuser --help`.
+  # When left blank, postgres will use the default role. This is
+  # the same name as the operating system user running Rails.
+  #username: goal_app_refactor
+
+  # The password associated with the postgres role (username).
+  #password:
+
+  # Connect on a TCP socket. Omitted by default since the client uses a
+  # domain socket that doesn't need configuration. Windows does not have
+  # domain sockets, so uncomment these lines.
+  #host: localhost
+
+  # The TCP port the server listens on. Defaults to 5432.
+  # If your server runs on a different port number, change accordingly.
+  #port: 5432
+
+  # Schema search path. The server defaults to $user,public
+  #schema_search_path: myapp,sharedapp,public
+
+  # Minimum log levels, in increasing order:
+  #   debug5, debug4, debug3, debug2, debug1,
+  #   log, notice, warning, error, fatal, and panic
+  # Defaults to warning.
+  #min_messages: notice
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: goal_app_refactor_test
+
+# As with config/credentials.yml, you never want to store sensitive information,
+# like your database password, in your source code. If your source code is
+# ever seen by anyone, they now have access to your database.
+#
+# Instead, provide the password or a full connection URL as an environment
+# variable when you boot the app. For example:
+#
+#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
+#
+# If the connection URL is provided in the special DATABASE_URL environment
+# variable, Rails will automatically merge its configuration values on top of
+# the values provided in this file. Alternatively, you can specify a connection
+# URL environment variable explicitly:
+#
+#   production:
+#     url: <%= ENV["MY_APP_DATABASE_URL"] %>
+#
+# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
+# for a full overview on how database connection configuration can be specified.
+#
+production:
+  <<: *default
+  database: goal_app_refactor_production
+  username: goal_app_refactor
+  password: <%= ENV["GOAL_APP_REFACTOR_DATABASE_PASSWORD"] %>
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/environment.rb b/rails/projects/goal_app_refactor/config/environment.rb
new file mode 100644
index 0000000..445c788
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/environment.rb
@@ -0,0 +1,5 @@
+# Load the Rails application.
+require_relative "application"
+
+# Initialize the Rails application.
+Rails.application.initialize!
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/environments/development.rb b/rails/projects/goal_app_refactor/config/environments/development.rb
new file mode 100644
index 0000000..851adc5
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/environments/development.rb
@@ -0,0 +1,62 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # In the development environment your application's code is reloaded any time
+  # it changes. This slows down response time but is perfect for development
+  # since you don't have to restart the web server when you make code changes.
+  config.cache_classes = false
+
+  # Do not eager load code on boot.
+  config.eager_load = false
+
+  # Show full error reports.
+  config.consider_all_requests_local = true
+
+  # Enable server timing
+  config.server_timing = true
+
+  # Enable/disable caching. By default caching is disabled.
+  # Run rails dev:cache to toggle caching.
+  if Rails.root.join("tmp/caching-dev.txt").exist?
+    config.action_controller.perform_caching = true
+    config.action_controller.enable_fragment_cache_logging = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      "Cache-Control" => "public, max-age=#{2.days.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
+
+  # Print deprecation notices to the Rails logger.
+  config.active_support.deprecation = :log
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raise an error on page load if there are pending migrations.
+  config.active_record.migration_error = :page_load
+
+  # Highlight code that triggered database queries in logs.
+  config.active_record.verbose_query_logs = true
+
+  # Suppress logger output for asset requests.
+  config.assets.quiet = true
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+
+  # Uncomment if you wish to allow Action Cable access from any origin.
+  # config.action_cable.disable_request_forgery_protection = true
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/environments/production.rb b/rails/projects/goal_app_refactor/config/environments/production.rb
new file mode 100644
index 0000000..6aee001
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/environments/production.rb
@@ -0,0 +1,75 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Code is not reloaded between requests.
+  config.cache_classes = true
+
+  # Eager load code on boot. This eager loads most of Rails and
+  # your application in memory, allowing both threaded web servers
+  # and those relying on copy on write to perform better.
+  # Rake tasks automatically ignore this option for performance.
+  config.eager_load = true
+
+  # Full error reports are disabled and caching is turned on.
+  config.consider_all_requests_local       = false
+  config.action_controller.perform_caching = true
+
+  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  # config.require_master_key = true
+
+  # Disable serving static files from the `/public` folder by default since
+  # Apache or NGINX already handles this.
+  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
+
+  # Compress CSS using a preprocessor.
+  # config.assets.css_compressor = :sass
+
+  # Do not fallback to assets pipeline if a precompiled asset is missed.
+  config.assets.compile = false
+
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.asset_host = "http://assets.example.com"
+
+  # Specifies the header that your server uses for sending files.
+  # config.action_dispatch.x_sendfile_header = "X-Sendfile" # for Apache
+  # config.action_dispatch.x_sendfile_header = "X-Accel-Redirect" # for NGINX
+
+  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
+  # config.force_ssl = true
+
+  # Include generic and useful information about system operation, but avoid logging too much
+  # information to avoid inadvertent exposure of personally identifiable information (PII).
+  config.log_level = :info
+
+  # Prepend all log lines with the following tags.
+  config.log_tags = [ :request_id ]
+
+  # Use a different cache store in production.
+  # config.cache_store = :mem_cache_store
+
+  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
+  # the I18n.default_locale when a translation cannot be found).
+  config.i18n.fallbacks = true
+
+  # Don't log any deprecations.
+  config.active_support.report_deprecations = false
+
+  # Use default logging formatter so that PID and timestamp are not suppressed.
+  config.log_formatter = ::Logger::Formatter.new
+
+  # Use a different logger for distributed setups.
+  # require "syslog/logger"
+  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
+
+  if ENV["RAILS_LOG_TO_STDOUT"].present?
+    logger           = ActiveSupport::Logger.new(STDOUT)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/environments/test.rb b/rails/projects/goal_app_refactor/config/environments/test.rb
new file mode 100644
index 0000000..5a05ef8
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/environments/test.rb
@@ -0,0 +1,51 @@
+require "active_support/core_ext/integer/time"
+
+# The test environment is used exclusively to run your application's
+# test suite. You never need to work with it otherwise. Remember that
+# your test database is "scratch space" for the test suite and is wiped
+# and recreated between test runs. Don't rely on the data there!
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Turn false under Spring and add config.action_view.cache_template_loading = true.
+  config.cache_classes = false
+  config.action_view.cache_template_loading = true
+
+  # Eager loading loads your whole application. When running a single test locally,
+  # this probably isn't necessary. It's a good idea to do in a continuous integration
+  # system, or in some way before deploying your code.
+  config.eager_load = ENV["CI"].present?
+
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = {
+    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
+  }
+
+  # Show full error reports and disable caching.
+  config.consider_all_requests_local       = true
+  config.action_controller.perform_caching = false
+  config.cache_store = :null_store
+
+  # Raise exceptions instead of rendering exception templates.
+  config.action_dispatch.show_exceptions = false
+
+  # Disable request forgery protection in test environment.
+  config.action_controller.allow_forgery_protection = false
+
+  # Print deprecation notices to the stderr.
+  config.active_support.deprecation = :stderr
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/initializers/assets.rb b/rails/projects/goal_app_refactor/config/initializers/assets.rb
new file mode 100644
index 0000000..bd8332f
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/initializers/assets.rb
@@ -0,0 +1,12 @@
+# Be sure to restart your server when you modify this file.
+
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = "1.0"
+
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/initializers/content_security_policy.rb b/rails/projects/goal_app_refactor/config/initializers/content_security_policy.rb
new file mode 100644
index 0000000..b713b2f
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/initializers/content_security_policy.rb
@@ -0,0 +1,25 @@
+# Be sure to restart your server when you modify this file.
+
+# Define an application-wide content security policy.
+# See the Securing Rails Applications Guide for more information:
+# https://guides.rubyonrails.org/security.html#content-security-policy-header
+
+# Rails.application.configure do
+#   config.content_security_policy do |policy|
+#     policy.default_src :self, :https
+#     policy.font_src    :self, :https, :data
+#     policy.img_src     :self, :https, :data
+#     policy.object_src  :none
+#     policy.script_src  :self, :https
+#     policy.style_src   :self, :https
+#     # Specify URI for violation reports
+#     # policy.report_uri "/csp-violation-report-endpoint"
+#   end
+#
+#   # Generate session nonces for permitted importmap and inline scripts
+#   config.content_security_policy_nonce_generator = ->(request) { request.session.id.to_s }
+#   config.content_security_policy_nonce_directives = %w(script-src)
+#
+#   # Report violations without enforcing the policy.
+#   # config.content_security_policy_report_only = true
+# end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/initializers/filter_parameter_logging.rb b/rails/projects/goal_app_refactor/config/initializers/filter_parameter_logging.rb
new file mode 100644
index 0000000..b4db5f6
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/initializers/filter_parameter_logging.rb
@@ -0,0 +1,8 @@
+# Be sure to restart your server when you modify this file.
+
+# Configure parameters to be filtered from the log file. Use this to limit dissemination of
+# sensitive information. See the ActiveSupport::ParameterFilter documentation for supported
+# notations and behaviors.
+Rails.application.config.filter_parameters += [
+  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
+]
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/initializers/inflections.rb b/rails/projects/goal_app_refactor/config/initializers/inflections.rb
new file mode 100644
index 0000000..df431d7
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/initializers/inflections.rb
@@ -0,0 +1,16 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new inflection rules using the following format. Inflections
+# are locale specific, and you may define rules for as many different
+# locales as you wish. All of these examples are active by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.plural /^(ox)$/i, "\\1en"
+#   inflect.singular /^(ox)en/i, "\\1"
+#   inflect.irregular "person", "people"
+#   inflect.uncountable %w( fish sheep )
+# end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym "RESTful"
+# end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/initializers/permissions_policy.rb b/rails/projects/goal_app_refactor/config/initializers/permissions_policy.rb
new file mode 100644
index 0000000..dd30019
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/initializers/permissions_policy.rb
@@ -0,0 +1,11 @@
+# Define an application-wide HTTP permissions policy. For further
+# information see https://developers.google.com/web/updates/2018/06/feature-policy
+#
+# Rails.application.config.permissions_policy do |f|
+#   f.camera      :none
+#   f.gyroscope   :none
+#   f.microphone  :none
+#   f.usb         :none
+#   f.fullscreen  :self
+#   f.payment     :self, "https://secure.example.com"
+# end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/locales/en.yml b/rails/projects/goal_app_refactor/config/locales/en.yml
new file mode 100644
index 0000000..30c9973
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/locales/en.yml
@@ -0,0 +1,33 @@
+# Files in the config/locales directory are used for internationalization
+# and are automatically loaded by Rails. If you want to use locales other
+# than English, add the necessary files in this directory.
+#
+# To use the locales, use `I18n.t`:
+#
+#     I18n.t "hello"
+#
+# In views, this is aliased to just `t`:
+#
+#     <%= t("hello") %>
+#
+# To use a different locale, set it with `I18n.locale`:
+#
+#     I18n.locale = :es
+#
+# This would use the information in config/locales/es.yml.
+#
+# The following keys must be escaped otherwise they will not be retrieved by
+# the default I18n backend:
+#
+# true, false, on, off, yes, no
+#
+# Instead, surround them with single quotes.
+#
+# en:
+#   "true": "foo"
+#
+# To learn more, please read the Rails Internationalization guide
+# available at https://guides.rubyonrails.org/i18n.html.
+
+en:
+  hello: "Hello world"
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/puma.rb b/rails/projects/goal_app_refactor/config/puma.rb
new file mode 100644
index 0000000..411b18d
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/puma.rb
@@ -0,0 +1,43 @@
+# Puma can serve each request in a thread from an internal thread pool.
+# The `threads` method setting takes two numbers: a minimum and maximum.
+# Any libraries that use thread pools should be configured to match
+# the maximum value specified for Puma. Default is set to 5 threads for minimum
+# and maximum; this matches the default thread size of Active Record.
+#
+max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
+min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count }
+threads min_threads_count, max_threads_count
+
+# Specifies the `worker_timeout` threshold that Puma will use to wait before
+# terminating a worker in development environments.
+#
+worker_timeout 3600 if ENV.fetch("RAILS_ENV", "development") == "development"
+
+# Specifies the `port` that Puma will listen on to receive requests; default is 3000.
+#
+port ENV.fetch("PORT") { 3000 }
+
+# Specifies the `environment` that Puma will run in.
+#
+environment ENV.fetch("RAILS_ENV") { "development" }
+
+# Specifies the `pidfile` that Puma will use.
+pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
+
+# Specifies the number of `workers` to boot in clustered mode.
+# Workers are forked web server processes. If using threads and workers together
+# the concurrency of the application would be max `threads` * `workers`.
+# Workers do not work on JRuby or Windows (both of which do not support
+# processes).
+#
+# workers ENV.fetch("WEB_CONCURRENCY") { 2 }
+
+# Use the `preload_app!` method when specifying a `workers` number.
+# This directive tells Puma to first boot the application and load code
+# before forking the application. This takes advantage of Copy On Write
+# process behavior so workers use less memory.
+#
+# preload_app!
+
+# Allow puma to be restarted by `bin/rails restart` command.
+plugin :tmp_restart
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/config/routes.rb b/rails/projects/goal_app_refactor/config/routes.rb
new file mode 100644
index 0000000..ada0adb
--- /dev/null
+++ b/rails/projects/goal_app_refactor/config/routes.rb
@@ -0,0 +1,15 @@
+Rails.application.routes.draw do
+  # Define your application routes per the DSL in https://guides.rubyonrails.org/routing.html
+
+  # Defines the root path route ("/")
+  root "users#index"
+
+  resource :session, only: [:new, :create, :destroy]
+  resources :users, only: [:index, :show, :new, :create]
+  resources :goals do
+    resources :cheers, only: [:create]
+  end
+  resources :cheers, only: [:index]
+  resources :user_comments, only: [:create]
+  resources :goal_comments, only: [:create]
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/db/migrate/20220601205619_create_users.rb b/rails/projects/goal_app_refactor/db/migrate/20220601205619_create_users.rb
new file mode 100644
index 0000000..190d4ff
--- /dev/null
+++ b/rails/projects/goal_app_refactor/db/migrate/20220601205619_create_users.rb
@@ -0,0 +1,13 @@
+class CreateUsers < ActiveRecord::Migration[7.0]
+  def change
+    create_table :users do |t|
+      t.string :username, null: false
+      t.string :session_token, null: false
+      t.string :password_digest, null: false
+
+      t.timestamps
+    end
+    add_index :users, :username, unique: true
+    add_index :users, :session_token, unique: true
+  end
+end
diff --git a/rails/projects/goal_app_refactor/db/migrate/20220601214017_create_goals.rb b/rails/projects/goal_app_refactor/db/migrate/20220601214017_create_goals.rb
new file mode 100644
index 0000000..cb6cbae
--- /dev/null
+++ b/rails/projects/goal_app_refactor/db/migrate/20220601214017_create_goals.rb
@@ -0,0 +1,14 @@
+class CreateGoals < ActiveRecord::Migration[7.0]
+  def change
+    create_table :goals do |t|
+      t.string :title, null: false
+      t.boolean :private, null: false, default: false
+      t.text :details
+      t.boolean :completed, null: false, default: false
+      t.references :author, null: false, foreign_key: { to_table: :users }
+
+      t.timestamps
+    end
+    add_index :goals, :title
+  end
+end
diff --git a/rails/projects/goal_app_refactor/db/migrate/20220601214145_create_user_comments.rb b/rails/projects/goal_app_refactor/db/migrate/20220601214145_create_user_comments.rb
new file mode 100644
index 0000000..5a3d855
--- /dev/null
+++ b/rails/projects/goal_app_refactor/db/migrate/20220601214145_create_user_comments.rb
@@ -0,0 +1,11 @@
+class CreateUserComments < ActiveRecord::Migration[7.0]
+  def change
+    create_table :user_comments do |t|
+      t.string :body, null: false
+      t.references :author, null: false, foreign_key: { to_table: :users }
+      t.references :recipient, null: false, foreign_key: { to_table: :users }
+
+      t.timestamps
+    end
+  end
+end
diff --git a/rails/projects/goal_app_refactor/db/migrate/20220601214235_create_goal_comments.rb b/rails/projects/goal_app_refactor/db/migrate/20220601214235_create_goal_comments.rb
new file mode 100644
index 0000000..2d99540
--- /dev/null
+++ b/rails/projects/goal_app_refactor/db/migrate/20220601214235_create_goal_comments.rb
@@ -0,0 +1,11 @@
+class CreateGoalComments < ActiveRecord::Migration[7.0]
+  def change
+    create_table :goal_comments do |t|
+      t.string :body, null: false
+      t.references :author, null: false, foreign_key: { to_table: :users }
+      t.references :goal, null: false, foreign_key: true
+
+      t.timestamps
+    end
+  end
+end
diff --git a/rails/projects/goal_app_refactor/db/migrate/20220601220401_create_cheers.rb b/rails/projects/goal_app_refactor/db/migrate/20220601220401_create_cheers.rb
new file mode 100644
index 0000000..02cda72
--- /dev/null
+++ b/rails/projects/goal_app_refactor/db/migrate/20220601220401_create_cheers.rb
@@ -0,0 +1,11 @@
+class CreateCheers < ActiveRecord::Migration[7.0]
+  def change
+    create_table :cheers do |t|
+      t.references :giver, null: false, foreign_key: { to_table: :users }
+      t.references :goal, null: false, foreign_key: true, index: false
+
+      t.timestamps
+    end
+    add_index :cheers, %i(goal_id giver_id), unique: true
+  end
+end
diff --git a/rails/projects/goal_app_refactor/db/migrate/20220601222505_add_cheer_count_to_users.rb b/rails/projects/goal_app_refactor/db/migrate/20220601222505_add_cheer_count_to_users.rb
new file mode 100644
index 0000000..403e275
--- /dev/null
+++ b/rails/projects/goal_app_refactor/db/migrate/20220601222505_add_cheer_count_to_users.rb
@@ -0,0 +1,5 @@
+class AddCheerCountToUsers < ActiveRecord::Migration[7.0]
+  def change
+    add_column :users, :cheer_count, :integer, null: false, default: 12
+  end
+end
diff --git a/rails/projects/goal_app_refactor/db/schema.rb b/rails/projects/goal_app_refactor/db/schema.rb
new file mode 100644
index 0000000..0b289a6
--- /dev/null
+++ b/rails/projects/goal_app_refactor/db/schema.rb
@@ -0,0 +1,76 @@
+# This file is auto-generated from the current state of the database. Instead
+# of editing this file, please use the migrations feature of Active Record to
+# incrementally modify your database, and then regenerate this schema definition.
+#
+# This file is the source Rails uses to define your schema when running `bin/rails
+# db:schema:load`. When creating a new database, `bin/rails db:schema:load` tends to
+# be faster and is potentially less error prone than running all of your
+# migrations from scratch. Old migrations may fail to apply correctly if those
+# migrations use external dependencies or application code.
+#
+# It's strongly recommended that you check this file into your version control system.
+
+ActiveRecord::Schema[7.0].define(version: 2022_08_02_132759) do
+  # These are extensions that must be enabled in order to support this database
+  enable_extension "plpgsql"
+
+  create_table "cheers", force: :cascade do |t|
+    t.bigint "giver_id", null: false
+    t.bigint "goal_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["giver_id"], name: "index_cheers_on_giver_id"
+    t.index ["goal_id", "giver_id"], name: "index_cheers_on_goal_id_and_giver_id", unique: true
+  end
+
+  create_table "goal_comments", force: :cascade do |t|
+    t.string "body", null: false
+    t.bigint "author_id", null: false
+    t.bigint "goal_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["author_id"], name: "index_goal_comments_on_author_id"
+    t.index ["goal_id"], name: "index_goal_comments_on_goal_id"
+  end
+
+  create_table "goals", force: :cascade do |t|
+    t.string "title", null: false
+    t.boolean "private", default: false, null: false
+    t.text "details"
+    t.boolean "completed", default: false, null: false
+    t.bigint "author_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["author_id"], name: "index_goals_on_author_id"
+    t.index ["title"], name: "index_goals_on_title"
+  end
+
+  create_table "user_comments", force: :cascade do |t|
+    t.string "body", null: false
+    t.bigint "author_id", null: false
+    t.bigint "recipient_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["author_id"], name: "index_user_comments_on_author_id"
+    t.index ["recipient_id"], name: "index_user_comments_on_recipient_id"
+  end
+
+  create_table "users", force: :cascade do |t|
+    t.string "username", null: false
+    t.string "session_token", null: false
+    t.string "password_digest", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.integer "cheer_count", default: 12, null: false
+    t.index ["session_token"], name: "index_users_on_session_token", unique: true
+    t.index ["username"], name: "index_users_on_username", unique: true
+  end
+
+  add_foreign_key "cheers", "goals"
+  add_foreign_key "cheers", "users", column: "giver_id"
+  add_foreign_key "goal_comments", "goals"
+  add_foreign_key "goal_comments", "users", column: "author_id"
+  add_foreign_key "goals", "users", column: "author_id"
+  add_foreign_key "user_comments", "users", column: "author_id"
+  add_foreign_key "user_comments", "users", column: "recipient_id"
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/db/seeds.rb b/rails/projects/goal_app_refactor/db/seeds.rb
new file mode 100644
index 0000000..6081fe2
--- /dev/null
+++ b/rails/projects/goal_app_refactor/db/seeds.rb
@@ -0,0 +1,42 @@
+# This file should contain all the record creation needed to seed the database with its default values.
+# The data can then be loaded with the bin/rails db:seed command (or created alongside the database with db:setup).
+#
+# Examples:
+#
+#   movies = Movie.create([{ name: "Star Wars" }, { name: "Lord of the Rings" }])
+#   Character.create(name: "Luke", movie: movies.first)
+require 'faker'
+
+ApplicationRecord.transaction do
+  puts "Destroying tables..."
+  Cheer.destroy_all
+  GoalComment.destroy_all
+  UserComment.destroy_all
+  Goal.destroy_all
+  User.destroy_all
+
+  puts "Resetting primary keys..."
+  %w(users goals user_comments goal_comments cheers).each do |table_name|
+    ApplicationRecord.connection.reset_pk_sequence!(table_name)
+  end
+
+  puts "Creating users..."
+  10.times do 
+    User.create!(
+      username: Faker::Internet.username,
+      password: Faker::Internet.password(min_length: 6, max_length:  12)
+    )
+  end
+
+  puts "Creating goals, comments, and cheers..."
+  User.all.each do |u|
+    2.times do
+      g = u.goals.create!(title: "read #{Faker::Book.title}")
+      g.comments.create!(author_id: User.all.sample.id, body: Faker::Company.buzzword + " goal!")
+      g.cheers.create!(giver_id: User.all.sample.id)
+    end
+  end
+  User.first.comments.create!(author: User.second, body: "Great work!")
+
+  puts "Done!"
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/helpers/application_helper.rb b/rails/projects/goal_app_refactor/helpers/application_helper.rb
new file mode 100644
index 0000000..de6be79
--- /dev/null
+++ b/rails/projects/goal_app_refactor/helpers/application_helper.rb
@@ -0,0 +1,2 @@
+module ApplicationHelper
+end
diff --git a/rails/projects/goal_app_refactor/lib/assets/.keep b/rails/projects/goal_app_refactor/lib/assets/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/lib/tasks/.keep b/rails/projects/goal_app_refactor/lib/tasks/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/log/.keep b/rails/projects/goal_app_refactor/log/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/public/404.html b/rails/projects/goal_app_refactor/public/404.html
new file mode 100644
index 0000000..cb93ac7
--- /dev/null
+++ b/rails/projects/goal_app_refactor/public/404.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The page you were looking for doesn't exist (404)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/404.html -->
+  <div class="dialog">
+    <div>
+      <h1>The page you were looking for doesn't exist.</h1>
+      <p>You may have mistyped the address or the page may have moved.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/public/422.html b/rails/projects/goal_app_refactor/public/422.html
new file mode 100644
index 0000000..aa1a374
--- /dev/null
+++ b/rails/projects/goal_app_refactor/public/422.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The change you wanted was rejected (422)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/422.html -->
+  <div class="dialog">
+    <div>
+      <h1>The change you wanted was rejected.</h1>
+      <p>Maybe you tried to change something you didn't have access to.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/public/500.html b/rails/projects/goal_app_refactor/public/500.html
new file mode 100644
index 0000000..0fd6fca
--- /dev/null
+++ b/rails/projects/goal_app_refactor/public/500.html
@@ -0,0 +1,66 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>We're sorry, but something went wrong (500)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/500.html -->
+  <div class="dialog">
+    <div>
+      <h1>We're sorry, but something went wrong.</h1>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/public/apple-touch-icon-precomposed.png b/rails/projects/goal_app_refactor/public/apple-touch-icon-precomposed.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/public/apple-touch-icon.png b/rails/projects/goal_app_refactor/public/apple-touch-icon.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/public/favicon.ico b/rails/projects/goal_app_refactor/public/favicon.ico
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/public/robots.txt b/rails/projects/goal_app_refactor/public/robots.txt
new file mode 100644
index 0000000..0285b2d
--- /dev/null
+++ b/rails/projects/goal_app_refactor/public/robots.txt
@@ -0,0 +1 @@
+# See https://www.robotstxt.org/robotstxt.html for documentation on how to use the robots.txt file
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/factories/cheers.rb b/rails/projects/goal_app_refactor/spec/factories/cheers.rb
new file mode 100644
index 0000000..60067ca
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/factories/cheers.rb
@@ -0,0 +1,16 @@
+# == Schema Information
+#
+# Table name: cheers
+#
+#  id         :bigint           not null, primary key
+#  giver_id   :bigint           not null
+#  goal_id    :bigint           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+FactoryBot.define do
+  factory :cheer do
+    giver { nil }
+    goal { nil }
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/factories/goal_comments.rb b/rails/projects/goal_app_refactor/spec/factories/goal_comments.rb
new file mode 100644
index 0000000..3aa6d20
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/factories/goal_comments.rb
@@ -0,0 +1,18 @@
+# == Schema Information
+#
+# Table name: goal_comments
+#
+#  id         :bigint           not null, primary key
+#  body       :string           not null
+#  author_id  :bigint           not null
+#  goal_id    :bigint           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+FactoryBot.define do
+  factory :goal_comment do
+    body { "MyString" }
+    author { nil }
+    goal { nil }
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/factories/goals.rb b/rails/projects/goal_app_refactor/spec/factories/goals.rb
new file mode 100644
index 0000000..e907499
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/factories/goals.rb
@@ -0,0 +1,28 @@
+# == Schema Information
+#
+# Table name: goals
+#
+#  id         :bigint           not null, primary key
+#  title      :string           not null
+#  private    :boolean          default(FALSE), not null
+#  details    :text
+#  completed  :boolean          default(FALSE), not null
+#  author_id  :bigint           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+FactoryBot.define do
+  factory :goal do
+    title { Faker::Lorem.words(number: 3).join(" ") }
+    details { Faker::Lorem.words(number: 5).join(" ") }
+    author { nil }
+
+    factory :private_goal do
+      private { true }
+    end
+
+    factory :completed_goal do
+      completed { true }
+    end
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/factories/user_comments.rb b/rails/projects/goal_app_refactor/spec/factories/user_comments.rb
new file mode 100644
index 0000000..89f197d
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/factories/user_comments.rb
@@ -0,0 +1,18 @@
+# == Schema Information
+#
+# Table name: user_comments
+#
+#  id           :bigint           not null, primary key
+#  body         :string           not null
+#  author_id    :bigint           not null
+#  recipient_id :bigint           not null
+#  created_at   :datetime         not null
+#  updated_at   :datetime         not null
+#
+FactoryBot.define do
+  factory :user_comment do
+    body { "MyString" }
+    author { nil }
+    recipient { nil }
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/factories/users.rb b/rails/projects/goal_app_refactor/spec/factories/users.rb
new file mode 100644
index 0000000..4290d47
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/factories/users.rb
@@ -0,0 +1,26 @@
+# == Schema Information
+#
+# Table name: users
+#
+#  id              :bigint           not null, primary key
+#  username        :string           not null
+#  session_token   :string           not null
+#  password_digest :string           not null
+#  created_at      :datetime         not null
+#  updated_at      :datetime         not null
+#  cheer_count     :integer          not null
+#
+FactoryBot.define do
+  factory :user do
+    username { Faker::Internet.unique.user_name }
+    password { "password" }
+
+    factory :user_hw do
+      username { "hello_world" }
+    end
+
+    factory :user_foo do
+      username { "foo_bar" }
+    end
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/models/goal_spec.rb b/rails/projects/goal_app_refactor/spec/models/goal_spec.rb
new file mode 100644
index 0000000..529f0e6
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/models/goal_spec.rb
@@ -0,0 +1,21 @@
+# == Schema Information
+#
+# Table name: goals
+#
+#  id         :bigint           not null, primary key
+#  title      :string           not null
+#  private    :boolean          default(FALSE), not null
+#  details    :text
+#  completed  :boolean          default(FALSE), not null
+#  author_id  :bigint           not null
+#  created_at :datetime         not null
+#  updated_at :datetime         not null
+#
+require 'rails_helper'
+
+RSpec.describe Goal, type: :model do
+  it { should validate_presence_of(:title) }
+  it { should belong_to(:author) }
+  it { should have_many(:comments).dependent(:destroy) }
+  it { should have_many(:cheers).dependent(:destroy) }
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/models/user_spec.rb b/rails/projects/goal_app_refactor/spec/models/user_spec.rb
new file mode 100644
index 0000000..87bce4f
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/models/user_spec.rb
@@ -0,0 +1,72 @@
+# == Schema Information
+#
+# Table name: users
+#
+#  id              :bigint           not null, primary key
+#  username        :string           not null
+#  session_token   :string           not null
+#  password_digest :string           not null
+#  created_at      :datetime         not null
+#  updated_at      :datetime         not null
+#  cheer_count     :integer          not null
+#
+require 'rails_helper'
+
+RSpec.describe User, type: :model do
+  subject(:gerald) do
+    User.create!(
+      username: "gerald",
+      password: "super_secret_password"
+    )
+  end
+
+  describe "session_token" do
+    it "is always set to a valid value before validation" do
+      gerald.session_token = nil
+      expect(gerald.valid?).to be true
+      expect(gerald.session_token).not_to be_nil
+    end
+  end
+
+  describe "password encryption" do
+    it "does not save passwords to the database" do
+      User.create!(username: "mary_mack", password: "abcdef")
+      user = User.find_by(username: "mary_mack")
+      expect(user.password).not_to eq("abcdef")
+    end
+
+    it "encrypts the password using BCrypt" do
+      expect(BCrypt::Password).to receive(:create)
+      User.new(username: "mary_mack", password: "abcdef")
+    end
+  end
+
+  describe "User.find_by_credentials" do
+    let!(:mary) { User.create!(username: "mary_mack", password: "abcdef") }
+
+    it "finds a user given the correct name and password" do
+      user = User.find_by_credentials("mary_mack", "abcdef")
+      expect(user.username).to eq("mary_mack")
+    end
+
+    it "returns nil if given an incorrect username" do
+      user = User.find_by_credentials("mary", "abcdef")
+      expect(user).to be_nil
+    end
+
+    it "returns nil if given an incorrect password" do
+      user = User.find_by_credentials("mary_mack", "ab")
+      expect(user).to be_nil
+    end
+  end
+
+  it { should validate_presence_of(:username) }
+  it { should validate_uniqueness_of(:username) }
+  it { should validate_length_of(:password).is_at_least(6).allow_nil }
+  it { should validate_numericality_of(:cheer_count).only_integer.is_greater_than_or_equal_to(0) }
+  it { should have_many(:goals).dependent(:destroy) }
+  it { should have_many(:authored_comments).dependent(:destroy) }
+  it { should have_many(:comments).dependent(:destroy) }
+  it { should have_many(:cheers_given).dependent(:destroy) }
+  it { should have_many(:cheers_received).through(:goals).dependent(false) }
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/rails_helper.rb b/rails/projects/goal_app_refactor/spec/rails_helper.rb
new file mode 100644
index 0000000..73a4270
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/rails_helper.rb
@@ -0,0 +1,78 @@
+# This file is copied to spec/ when you run 'rails generate rspec:install'
+require 'spec_helper'
+ENV['RAILS_ENV'] ||= 'test'
+require_relative '../config/environment'
+# Prevent database truncation if the environment is production
+abort("The Rails environment is running in production mode!") if Rails.env.production?
+require 'rspec/rails'
+# Add additional requires below this line. Rails is not loaded until this point!
+require 'shoulda-matchers'
+require 'capybara/rspec'
+
+# Requires supporting ruby files with custom matchers and macros, etc, in
+# spec/support/ and its subdirectories. Files matching `spec/**/*_spec.rb` are
+# run as spec files by default. This means that files in spec/support that end
+# in _spec.rb will both be required and run as specs, causing the specs to be
+# run twice. It is recommended that you do not name files matching this glob to
+# end with _spec.rb. You can configure this pattern with the --pattern
+# option on the command line or in ~/.rspec, .rspec or `.rspec-local`.
+#
+# The following line is provided for convenience purposes. It has the downside
+# of increasing the boot-up time by auto-requiring all files in the support
+# directory. Alternatively, in the individual `*_spec.rb` files, manually
+# require only the support files necessary.
+#
+Dir[Rails.root.join('spec', 'support', '**', '*.rb')].sort.each { |f| require f }
+
+# Checks for pending migrations and applies them before tests are run.
+# If you are not using ActiveRecord, you can remove these lines.
+begin
+  ActiveRecord::Migration.maintain_test_schema!
+rescue ActiveRecord::PendingMigrationError => e
+  puts e.to_s.strip
+  exit 1
+end
+RSpec.configure do |config|
+  config.include FactoryBot::Syntax::Methods
+  config.include AuthSystemHelper, type: :system
+  config.include AuthRequestHelper, type: :request
+  config.include GoalSystemHelper, type: :system
+  config.include GoalRequestHelper, type: :request
+  # Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
+  config.fixture_path = "#{::Rails.root}/spec/fixtures"
+
+  # If you're not using ActiveRecord, or you'd prefer not to run each of your
+  # examples within a transaction, remove the following line or assign false
+  # instead of true.
+  config.use_transactional_fixtures = true
+
+  # You can uncomment this line to turn off ActiveRecord support entirely.
+  # config.use_active_record = false
+
+  # RSpec Rails can automatically mix in different behaviours to your tests
+  # based on their file location, for example enabling you to call `get` and
+  # `post` in specs under `spec/controllers`.
+  #
+  # You can disable this behaviour by removing the line below, and instead
+  # explicitly tag your specs with their type, e.g.:
+  #
+  #     RSpec.describe UsersController, type: :controller do
+  #       # ...
+  #     end
+  #
+  # The different available types are documented in the features, such as in
+  # https://relishapp.com/rspec/rspec-rails/docs
+  config.infer_spec_type_from_file_location!
+
+  # Filter lines from Rails gems in backtraces.
+  config.filter_rails_from_backtrace!
+  # arbitrary gems may also be filtered via:
+  # config.filter_gems_from_backtrace("gem name")
+end
+
+Shoulda::Matchers.configure do |config|
+  config.integrate do |with|
+    with.test_framework :rspec
+    with.library :rails
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/requests/goals_spec.rb b/rails/projects/goal_app_refactor/spec/requests/goals_spec.rb
new file mode 100644
index 0000000..6630b78
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/requests/goals_spec.rb
@@ -0,0 +1,188 @@
+require 'rails_helper'
+
+RSpec.describe "Goals", type: :request do
+  let(:hello_world) { create(:user_hw) }
+
+  describe 'GET /goals (#index)' do
+    context 'when logged in' do
+      before do
+        log_in_as(hello_world)
+      end
+      
+      it "displays the goals index" do
+        build_three_goals(hello_world)
+        get goals_url
+        verify_three_goals
+      end
+    end
+
+    context 'when logged out' do
+      it 'redirects to the login page' do
+        get goals_url
+        expect(response).to redirect_to(new_user_url)
+      end
+    end
+  end
+  
+  describe 'GET /goals/:id (#show)' do
+    context 'when logged in' do
+      before do
+        log_in_as(hello_world)
+      end
+
+      it "shows the specified goal" do
+        goal = create(:goal, title: "Goal 1", author: hello_world)
+        get goal_url(goal)
+        expect(response.body).to include("Goal 1")
+      end
+    end
+
+    context 'when logged out' do
+      it 'redirects to the login page' do
+        get goals_url
+        expect(response).to redirect_to(new_user_url)
+      end
+    end
+  end
+
+  describe 'GET /goals/new (#new)' do
+    context 'when logged in' do
+      before do
+        log_in_as(hello_world)
+      end
+
+      it 'renders the new Goals page' do
+        get new_goal_url
+        expect(response.body).to include('New Goal')
+      end
+    end
+
+    context 'when logged out' do
+      it 'redirects to the login page' do
+        get new_goal_url
+        expect(response).to redirect_to(new_user_url)
+      end
+    end
+  end
+
+  describe 'POST /goals (#create)' do
+    let(:hello_world) { create(:user_hw) }
+
+    context 'when logged out' do
+      it 'redirects to the login page' do
+        post goals_url, params: { goal: {} }
+        expect(response).to redirect_to(new_user_url)
+      end
+    end
+
+    context 'when logged in' do
+      before do
+        log_in_as(hello_world)
+      end
+
+      context 'with invalid params' do
+        it 'validates the presence of title' do
+          post goals_url, params: { goal: { title: "" } }
+          expect(response.body).to include('New Goal')
+          expect(CGI.unescapeHTML(response.body)).to include("Title can't be blank")
+        end
+      end
+
+      context 'with valid params' do
+        it 'redirects to the goal show page' do
+          post goals_url, params: { goal: { title: 'teehee', details: 'cats.com' } }
+          expect(response).to redirect_to(goal_url(Goal.last))
+        end
+      end
+    end
+  end
+
+  describe 'GET /goals/:id/edit (#edit)' do
+    context 'when logged in' do
+      before do
+        log_in_as(hello_world)
+      end
+
+      it 'renders a goal\'s edit page' do
+        goal = create(:goal, author: hello_world)
+        get edit_goal_url(goal)
+        expect(response.body).to include('Edit Goal')
+        expect(response.body).to include(goal.title)
+      end
+    end
+
+    context 'when logged out' do
+      it 'redirects to the login page' do
+        get goals_url
+        expect(response).to redirect_to(new_user_url)
+      end
+    end
+  end
+
+
+  describe 'PATCH /goals/:id (#update)' do
+    let(:goal) { create(:goal, author: hello_world) }
+    
+    context 'when logged in' do
+      before do
+        log_in_as(hello_world)
+      end
+
+      context 'with invalid params' do
+        it 'stays on the edit page' do
+          patch goal_url(goal), params: { goal: { title: "" } }
+          expect(response.body).to include('Edit Goal')
+        end
+        
+        it 'reports the error' do
+          patch goal_url(goal), params: { goal: { title: "" } }
+          expect(CGI.unescapeHTML(response.body)).to include("Title can't be blank")
+        end
+      end
+
+      context 'with valid params' do
+        it 'redirects to the goal show page' do
+          patch goal_url(goal), params: { goal: { title: 'teehee', details: 'cats.com' } }
+          expect(response).to redirect_to(goal_url(goal))
+        end
+      end
+    end
+
+    context 'when logged out' do
+      it 'redirects to the login page' do
+        patch goal_url(goal)
+        expect(response).to redirect_to(new_user_url)
+      end
+    end
+  end
+
+  describe 'DELETE /goals/:id (#destroy)' do
+    context 'when logged in' do
+      let(:goal) { create(:goal, author: hello_world) } # == FactoryBot.create
+
+      before do
+        log_in_as(hello_world)
+      end
+
+      it "deletes the goal" do
+        expect(Goal.find_by(id: goal.id)).to eq(goal)
+        delete goal_url(goal)
+        expect(Goal.find_by(id: goal.id)).to be_nil
+      end
+
+      it "redirects to the goal index" do
+        delete goal_url(goal)
+        expect(response).to redirect_to(goals_url)
+      end
+    end
+
+    context 'when logged out' do
+      let(:goal) { create(:goal, author: hello_world) }
+
+      it 'redirects to the login page' do
+        delete goal_url(goal)
+        expect(response).to redirect_to(new_user_url)
+      end
+    end
+  end
+end  
diff --git a/rails/projects/goal_app_refactor/spec/requests/users_spec.rb b/rails/projects/goal_app_refactor/spec/requests/users_spec.rb
new file mode 100644
index 0000000..fe3bced
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/requests/users_spec.rb
@@ -0,0 +1,80 @@
+require 'rails_helper'
+
+RSpec.describe "Users", type: :request do
+  subject(:user) do
+    User.create!(
+      username: "jill_bruce",
+      password: "password"
+    )
+  end
+
+  describe "GET /users (#index)" do
+    it "renders the index template" do
+      get users_url
+      expect(response.body).to include("Users")
+    end
+  end
+
+  describe "GET /users/:id (#show)" do
+    it "renders the show template" do
+      get user_url(user)
+      expect(response.body).to include("Jill_bruce")
+    end
+  end
+  
+  describe "GET /users/new (#new)" do
+    it "renders the new template" do
+      get new_user_url
+      expect(response.body).to include("Sign Up!")
+    end
+  end
+
+  describe "POST /users (#create)" do
+    context "with invalid params" do
+      it "validates the presence of the user's username" do
+        post users_url, params: {
+          user: {
+            username: "",
+            password: "password"
+          }
+        }
+        expect(response.body).to include("Sign Up!")
+        expect(CGI.unescapeHTML(response.body)).to include("Username can't be blank")
+      end
+      
+      it "validates the presence of the user's password" do
+        post users_url, params: {
+          user: {
+            username: "jill_bruce",
+            password: ""
+          }
+        }
+        expect(response.body).to include("Sign Up!")
+        expect(response.body).to include("Password is too short")
+      end
+
+      it "validates that the password is at least 6 characters long" do
+        post users_url, params: {
+          user: {
+            username: "jill_bruce",
+            password: "short"
+          }
+        }
+        expect(response.body).to include("Sign Up!")
+        expect(response.body).to include("Password is too short")
+      end
+    end
+
+    context "with valid params" do
+      it "redirects user to user's show page on success" do
+        post users_url, params: {
+          user: {
+            username: "jill_bruce",
+            password: "password"
+          }
+        }
+        expect(response).to redirect_to(user_url(User.last))
+      end
+    end
+  end
+end
diff --git a/rails/projects/goal_app_refactor/spec/spec_helper.rb b/rails/projects/goal_app_refactor/spec/spec_helper.rb
new file mode 100644
index 0000000..ce00267
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/spec_helper.rb
@@ -0,0 +1,94 @@
+# This file was generated by the `rails generate rspec:install` command. Conventionally, all
+# specs live under a `spec` directory, which RSpec adds to the `$LOAD_PATH`.
+# The generated `.rspec` file contains `--require spec_helper` which will cause
+# this file to always be loaded, without a need to explicitly require it in any
+# files.
+#
+# Given that it is always loaded, you are encouraged to keep this file as
+# light-weight as possible. Requiring heavyweight dependencies from this file
+# will add to the boot time of your test suite on EVERY test run, even for an
+# individual file that may not need all of that loaded. Instead, consider making
+# a separate helper file that requires the additional dependencies and performs
+# the additional setup, and require it from the spec files that actually need
+# it.
+#
+# See https://rubydoc.info/gems/rspec-core/RSpec/Core/Configuration
+RSpec.configure do |config|
+  # rspec-expectations config goes here. You can use an alternate
+  # assertion/expectation library such as wrong or the stdlib/minitest
+  # assertions if you prefer.
+  config.expect_with :rspec do |expectations|
+    # This option will default to `true` in RSpec 4. It makes the `description`
+    # and `failure_message` of custom matchers include text for helper methods
+    # defined using `chain`, e.g.:
+    #     be_bigger_than(2).and_smaller_than(4).description
+    #     # => "be bigger than 2 and smaller than 4"
+    # ...rather than:
+    #     # => "be bigger than 2"
+    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
+  end
+
+  # rspec-mocks config goes here. You can use an alternate test double
+  # library (such as bogus or mocha) by changing the `mock_with` option here.
+  config.mock_with :rspec do |mocks|
+    # Prevents you from mocking or stubbing a method that does not exist on
+    # a real object. This is generally recommended, and will default to
+    # `true` in RSpec 4.
+    mocks.verify_partial_doubles = true
+  end
+
+  # This option will default to `:apply_to_host_groups` in RSpec 4 (and will
+  # have no way to turn it off -- the option exists only for backwards
+  # compatibility in RSpec 3). It causes shared context metadata to be
+  # inherited by the metadata hash of host groups and examples, rather than
+  # triggering implicit auto-inclusion in groups with matching metadata.
+  config.shared_context_metadata_behavior = :apply_to_host_groups
+
+# The settings below are suggested to provide a good initial experience
+# with RSpec, but feel free to customize to your heart's content.
+=begin
+  # This allows you to limit a spec run to individual examples or groups
+  # you care about by tagging them with `:focus` metadata. When nothing
+  # is tagged with `:focus`, all examples get run. RSpec also provides
+  # aliases for `it`, `describe`, and `context` that include `:focus`
+  # metadata: `fit`, `fdescribe` and `fcontext`, respectively.
+  config.filter_run_when_matching :focus
+
+  # Allows RSpec to persist some state between runs in order to support
+  # the `--only-failures` and `--next-failure` CLI options. We recommend
+  # you configure your source control system to ignore this file.
+  config.example_status_persistence_file_path = "spec/examples.txt"
+
+  # Limits the available syntax to the non-monkey patched syntax that is
+  # recommended. For more details, see:
+  # https://relishapp.com/rspec/rspec-core/docs/configuration/zero-monkey-patching-mode
+  config.disable_monkey_patching!
+
+  # Many RSpec users commonly either run the entire suite or an individual
+  # file, and it's useful to allow more verbose output when running an
+  # individual spec file.
+  if config.files_to_run.one?
+    # Use the documentation formatter for detailed output,
+    # unless a formatter has already been configured
+    # (e.g. via a command-line flag).
+    config.default_formatter = "doc"
+  end
+
+  # Print the 10 slowest examples and example groups at the
+  # end of the spec run, to help surface which specs are running
+  # particularly slow.
+  config.profile_examples = 10
+
+  # Run specs in random order to surface order dependencies. If you find an
+  # order dependency and want to debug it, you can fix the order by providing
+  # the seed, which is printed after each run.
+  #     --seed 1234
+  config.order = :random
+
+  # Seed global randomization in this process using the `--seed` CLI option.
+  # Setting this allows you to use `--seed` to deterministically reproduce
+  # test failures related to randomization by passing the same `--seed` value
+  # as the one that triggered the failure.
+  Kernel.srand config.seed
+=end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/support/request/auth_request_helper.rb b/rails/projects/goal_app_refactor/spec/support/request/auth_request_helper.rb
new file mode 100644
index 0000000..bb86fa6
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/support/request/auth_request_helper.rb
@@ -0,0 +1,10 @@
+module AuthRequestHelper
+  def log_in_as(user)
+    post session_url, params: { 
+      user: {
+        username: user.username,
+        password: user.password
+      }
+    }
+  end
+end
diff --git a/rails/projects/goal_app_refactor/spec/support/request/goal_request_helper.rb b/rails/projects/goal_app_refactor/spec/support/request/goal_request_helper.rb
new file mode 100644
index 0000000..f7b0419
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/support/request/goal_request_helper.rb
@@ -0,0 +1,13 @@
+module GoalRequestHelper
+  def build_three_goals(user)
+    create(:goal, title: "pickle a pepper", author: user) # == FactoryBot.create
+    create(:goal, title: "get octocat autograph", author: user)
+    create(:goal, title: "bake a cake", author: user)
+  end
+
+  def verify_three_goals
+      expect(response.body).to include("pickle a pepper")
+      expect(response.body).to include("get octocat autograph")
+      expect(response.body).to include("bake a cake")
+  end
+end
diff --git a/rails/projects/goal_app_refactor/spec/support/system/auth_system_helper.rb b/rails/projects/goal_app_refactor/spec/support/system/auth_system_helper.rb
new file mode 100644
index 0000000..3537ad8
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/support/system/auth_system_helper.rb
@@ -0,0 +1,15 @@
+module AuthSystemHelper
+  def log_in_as(user)
+    visit new_session_url
+    fill_in "Username", with: user.username
+    fill_in "Password", with: "password"
+    click_button "Log In"
+  end
+
+  def sign_up_as(username)
+    visit new_user_url
+    fill_in "Username", with: username
+    fill_in "Password", with: "password"
+    click_button "Sign Up"
+  end
+end
diff --git a/rails/projects/goal_app_refactor/spec/support/system/cheer_system_helper.rb b/rails/projects/goal_app_refactor/spec/support/system/cheer_system_helper.rb
new file mode 100644
index 0000000..d930321
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/support/system/cheer_system_helper.rb
@@ -0,0 +1,13 @@
+module CheerSystemHelper
+  def give_cheer_to(cheered_user)
+    visit user_url(cheered_user)
+    click_button "Cheer!"
+  end
+
+  def give_another_cheer
+    next_user = create(:user) # == FactoryBot.create
+    create(:goal, author: next_user)
+    visit user_url(next_user)
+    click_button "Cheer!"
+  end
+end
diff --git a/rails/projects/goal_app_refactor/spec/support/system/goal_system_helper.rb b/rails/projects/goal_app_refactor/spec/support/system/goal_system_helper.rb
new file mode 100644
index 0000000..958045d
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/support/system/goal_system_helper.rb
@@ -0,0 +1,22 @@
+module GoalSystemHelper
+  def submit_new_goal(goal_title, privacy = {private: false})
+    visit new_goal_url
+    fill_in "Title", with: goal_title
+    if privacy[:private]
+      check "Private?"
+    end
+    click_button "New Goal"
+  end
+
+  def build_three_goals(user)
+    create(:goal, title: "pickle a pepper", author: user) # == FactoryBot.create
+    create(:goal, title: "get octocat's autograph", author: user)
+    create(:goal, title: "bake a cake", author: user)
+  end
+
+  def verify_three_goals
+    expect(page).to have_content "pickle a pepper"
+    expect(page).to have_content "get octocat's autograph"
+    expect(page).to have_content "bake a cake"
+  end
+end
diff --git a/rails/projects/goal_app_refactor/spec/system/auth_spec.rb b/rails/projects/goal_app_refactor/spec/system/auth_spec.rb
new file mode 100644
index 0000000..50720bb
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/system/auth_spec.rb
@@ -0,0 +1,43 @@
+require 'rails_helper'
+
+RSpec.describe "Auth", type: :system do
+  before do
+    driven_by(:rack_test)
+  end
+
+  describe "the signup process" do
+    it "has a new user page" do
+      visit new_user_url
+      expect(page).to have_content "Sign Up!"
+    end
+
+    it "shows username on the homepage after signup" do
+      sign_up_as('hello_world')
+      expect(page).to have_content "Welcome hello_world"
+    end
+  end
+
+  describe "logging in" do
+    let(:hello_world) { create(:user_hw) } # == FactoryBot.create
+
+    it "shows username on the homepage after login" do
+      log_in_as(hello_world)
+      expect(page).to have_content "Welcome hello_world"
+    end
+  end
+
+  describe "logging out" do
+    let!(:hello_world) { create(:user_hw) } # == FactoryBot.create
+
+    it "begins with logged out state" do
+      visit root_url
+      expect(page).to have_content "Log In"
+    end
+
+    it "doesn't show username on the homepage after logout" do
+      log_in_as(hello_world)
+      click_button "Log Out"
+      expect(page).not_to have_content "hello_world"
+    end
+  end
+end
diff --git a/rails/projects/goal_app_refactor/spec/system/cheers_spec.rb b/rails/projects/goal_app_refactor/spec/system/cheers_spec.rb
new file mode 100644
index 0000000..d0172dc
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/system/cheers_spec.rb
@@ -0,0 +1,96 @@
+require 'rails_helper'
+
+RSpec.describe "Cheers", type: :system do
+  # Since `CheerSystemHelper` is really only needed for this test suite, it has
+  # been included here rather than in the config section of rails_helper.rb
+  # (which would effectively include it inside every system test suite).
+  include CheerSystemHelper
+  before do
+    driven_by(:rack_test)
+  end
+
+  describe "giving cheers" do
+    let!(:hello_world) { create(:user_hw) } # == FactoryBot.create
+    let!(:foo_bar) { create(:user_foo) }
+
+    let!(:hw_goal) { create(:goal, author: hello_world) }
+    let!(:foo_goal) { create(:goal, author: foo_bar) }
+
+    before do
+      log_in_as(foo_bar)
+    end
+
+    it "lets a user give a cheer for another user's goal" do
+      give_cheer_to(hello_world)
+      expect(page).to have_content("You cheered hello_world's goal!")
+      expect(page).not_to have_button "Cheer!"
+    end
+
+    it "does not let a user cheer their own goals" do
+      visit goal_url(foo_goal)
+      expect(page).not_to have_button "Cheer!"
+      visit user_url(foo_bar)
+      expect(page).not_to have_button "Cheer!"
+    end
+
+    it "does not let the user cheer the same goal twice" do
+      give_cheer_to(hello_world)
+      expect(page).not_to have_button "Cheer!"
+    end
+  end
+
+  describe "viewing my cheers" do
+    let!(:hello_world) { create(:user_hw) } # == FactoryBot.create
+    let!(:foo_bar) { create(:user_foo) }
+    let!(:hw_goal) { create(:goal, author: hello_world) }
+
+    before(:each) do
+      create(:cheer, giver: foo_bar, goal: hw_goal) # == FactoryBot.create
+      log_in_as(hello_world)
+    end
+
+    it "lets a user see the number of cheers left for their goal" do
+      visit goal_url(hw_goal)
+      expect(page).to have_content "Cheers: 1"
+    end
+
+    it "has a cheer index that shows the cheers with their info" do
+      visit cheers_url
+      expect(page).to have_content "Cheer given by:"
+      expect(page).to have_content foo_bar.username
+      expect(page).to have_content "For goal of:"
+      expect(page).to have_content hw_goal.title
+    end
+  end
+
+  describe "limit on cheers" do
+    let!(:hello_world) { create(:user_hw) } # == FactoryBot.create
+    let!(:foo_bar) { create(:user_foo) }
+    let!(:hw_goal) { create(:goal, author: hello_world) }
+
+    before do
+      log_in_as(foo_bar)
+      visit user_url(hello_world)
+      @limit = page.find("#cheer-limit").text.to_i
+    end
+
+    it "displays remaining cheers for the day to logged-in user on profile" do
+      expect((@limit > 0)).to be_truthy
+    end
+
+    it "does not allow giving more cheers than the limit" do
+      until @limit == 0
+        give_another_cheer
+        @limit = page.find("#cheer-limit").text.to_i
+      end
+      # attempt going over the cheer limit
+      expect(page).not_to have_button "Cheer!"
+    end
+  end
+end
+
+# More great ideas for specs:
+# Each goal should have its own cheer button
+# Pushing the 'Cheer' button for one goal should not change other goals
+# Pushing the button only decreases cheer count by 1
+# Allow removing of cheers
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/system/comments_spec.rb b/rails/projects/goal_app_refactor/spec/system/comments_spec.rb
new file mode 100644
index 0000000..4633e83
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/system/comments_spec.rb
@@ -0,0 +1,48 @@
+require 'rails_helper'
+
+RSpec.describe "Commenting" do
+  # The `config.include FactoryBot::Syntax::Methods` line in __rails_helper.rb__
+  # means that you don't have to preface FactoryBot commands with `FactoryBot.`.
+  # The code in this file includes `FactoryBot.` just to illustrate how it
+  # would be done without that confguration line. (`FactoryBot.` still works,
+  # even with the line!)
+  let!(:hello_world) { FactoryBot.create(:user_hw) }
+  let!(:foo_bar) { FactoryBot.create(:user, username: "foo_bar") }
+  let!(:foo_goal) do
+    FactoryBot.create(:goal, author: foo_bar)
+  end
+
+  before do
+    driven_by(:rack_test)
+    log_in_as(hello_world)
+    visit user_url(foo_bar)
+  end
+
+  # shared_examples are another way to DRY out your specs
+  # have some docs:
+  # https://www.relishapp.com/rspec/rspec-core/docs/example-groups/shared-examples
+  shared_examples "comment" do
+    it "should have a form for adding a new comment" do
+      expect(page).to have_content "New Comment"
+      expect(page).to have_field "Comment"
+    end
+
+    it "should save the comment when a user submits one" do
+      fill_in "Comment", with: "my magical comment!"
+      click_on "Save Comment"
+      expect(page).to have_content "my magical comment!"
+    end
+  end
+
+  describe "user profile comment" do
+    it_behaves_like "comment"
+  end
+
+  describe "goal comment" do
+    before do
+      click_on foo_goal.title
+    end
+
+    it_behaves_like "comment"
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/spec/system/goals_completeness_spec.rb b/rails/projects/goal_app_refactor/spec/system/goals_completeness_spec.rb
new file mode 100644
index 0000000..e9339d0
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/system/goals_completeness_spec.rb
@@ -0,0 +1,97 @@
+require 'rails_helper'
+
+RSpec.describe "Goal completeness tracking" do
+  let!(:hello_world) { create(:user_hw) } # == FactoryBot.create
+  let(:foo_bar) { create(:user_foo) }
+  let!(:hw_goal) { create(:goal, author: hello_world) }
+
+  before do
+    driven_by(:rack_test)
+    log_in_as(hello_world)
+  end
+
+  describe "goals start out uncompleted" do
+    context "on the goal show page" do
+      it "starts as not completed" do
+        visit goal_url(hw_goal)
+        expect(page).to have_content("Ongoing")
+      end
+    end
+
+    context "on the goal index page" do
+      it "starts as not completed" do
+        visit goals_url
+        expect(page).to have_content("Ongoing")
+      end
+    end
+
+    context "on the user's profile page" do
+      it "starts as not completed" do
+        visit user_url(hello_world)
+        expect(page).to have_content("Ongoing")
+      end
+    end
+  end
+
+  describe "marking a goal as completed" do
+    context "on the goal show page" do
+      it "allows user to change goal to completed" do
+        visit goal_url(hw_goal)
+        click_button "goal_#{hw_goal.id}_completed"
+        expect(page).to have_content("Complete")
+      end
+
+      it "redirects to the same page after updating goal" do
+        visit goal_url(hw_goal)
+        click_button "goal_#{hw_goal.id}_completed"
+        expect(page).to have_content("Goal:")
+        expect(page).to have_content("Title:")
+        expect(page).to have_content(hw_goal.title)
+      end
+
+      it "disallows editing completeness when it is not your goal" do
+        click_button "Log Out"
+        log_in_as(foo_bar)
+        visit goal_url(hw_goal)
+        expect(page).not_to have_button("Complete")
+      end
+    end
+
+    context "on the goal index page" do
+      it "allows user to change goal to completed" do
+        visit goals_url
+        click_button "goal_#{hw_goal.id}_completed"
+        expect(page).to have_content("Complete")
+      end
+
+      it "redirects to the same page after updating goal" do
+        visit goals_url
+        click_button "goal_#{hw_goal.id}_completed"
+        expect(page).to have_content("Your Goals")
+      end
+    end
+
+    context "on the user's profile page" do
+      it "allows user to change goal to completed" do
+        visit user_url(hello_world)
+        click_button "goal_#{hw_goal.id}_completed"
+        expect(page).to have_content("Complete")
+      end
+
+      it "redirects to the same page after updating goal" do
+        visit user_url(hello_world)
+        click_button "goal_#{hw_goal.id}_completed"
+        expect(page).to have_content("Complete")
+        expect(page).to have_content("Hello_world's Profile")
+        expect(page).to have_content("Hello_world's Goals:")
+      end
+
+      it "disallows editing completeness when it is not your goal" do
+        click_button "Log Out"
+        log_in_as(foo_bar)
+        visit user_url(hello_world)
+        expect(page).not_to have_button("Complete")
+      end
+    end
+  end
+end
diff --git a/rails/projects/goal_app_refactor/spec/system/goals_crud_spec.rb b/rails/projects/goal_app_refactor/spec/system/goals_crud_spec.rb
new file mode 100644
index 0000000..aa1da3e
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/system/goals_crud_spec.rb
@@ -0,0 +1,60 @@
+require 'rails_helper'
+
+RSpec.describe "CRUD of goals" do
+  let!(:hello_world) { create(:user_hw) } # == FactoryBot.create
+
+  before do
+    driven_by(:rack_test)
+    log_in_as(hello_world)
+  end
+
+  describe "creating goals" do
+    it "should have a page for creating a new goal" do
+      visit new_goal_url
+      expect(page).to have_content "New Goal"
+    end
+
+    it "should show the new goal after creation" do
+      submit_new_goal("have some toes")
+      expect(page).to have_content "have some toes"
+      expect(page).to have_content "Goal saved!"
+    end
+  end
+
+  describe "reading goals" do
+    it "should list goals" do
+      build_three_goals(hello_world)
+      visit goals_url
+      verify_three_goals
+    end
+  end
+
+  describe "updating goals" do
+    let(:goal) { create(:goal, author: hello_world) } # == FactoryBot.create
+
+    it "should have a page for updating an existing goal" do
+      visit edit_goal_url(goal)
+      expect(page).to have_content "Edit Goal"
+      expect(find_field('Title').value).to eq(goal.title)
+    end
+
+    it "should show the updated goal after changes are saved" do
+      visit edit_goal_url(goal)
+      fill_in "Title", with: "visit the sun"
+      click_button "Update Goal"
+      expect(page).not_to have_content "Edit Goal"
+      expect(page).to have_content "Goal updated!"
+      expect(page).to have_content "visit the sun"
+    end
+  end
+
+  describe "deleting goals" do
+    it "should allow the deletion of a goal" do
+      build_three_goals(hello_world)
+      visit goals_url
+      click_button "delete 'pickle a pepper' goal"
+      expect(page).not_to have_content "pickle a pepper"
+      expect(page).to have_content "Goal deleted!"
+    end
+  end
+end
diff --git a/rails/projects/goal_app_refactor/spec/system/goals_privacy_spec.rb b/rails/projects/goal_app_refactor/spec/system/goals_privacy_spec.rb
new file mode 100644
index 0000000..d62831d
--- /dev/null
+++ b/rails/projects/goal_app_refactor/spec/system/goals_privacy_spec.rb
@@ -0,0 +1,52 @@
+require 'rails_helper'
+
+RSpec.describe "Goal privacy" do
+  before do
+    driven_by(:rack_test)
+  end
+  
+  let!(:hello_world) { create(:user_hw) } # == FactoryBot.create
+  let!(:foo_bar) { create(:user_foo) }
+
+  describe "public goals" do
+    let!(:hw_goal) { create(:goal, author: hello_world) } # == FactoryBot.create
+
+    it "should create public goals by default" do
+      log_in_as(hello_world)
+      submit_new_goal("build a tesla coil")
+      expect(page).to have_content "Public"
+    end
+
+    it "shows public goals when logged out" do
+      visit user_url(hello_world)
+      expect(page).to have_content hw_goal.title
+    end
+
+    it "allows other users to see public goals" do
+      log_in_as(foo_bar)
+      visit user_url(hello_world)
+      expect(page).to have_content hw_goal.title
+    end
+  end
+
+  describe "private goals" do
+    let!(:hw_private_goal) { create(:private_goal, author: hello_world) } # == FactoryBot.create
+
+    it "allows creating private goals" do
+      log_in_as(hello_world)
+      visit goal_url(hw_private_goal)
+      expect(page).to have_content "Private"
+    end
+
+    it "hides private goals when logged out" do
+      visit user_url(hello_world)
+      expect(page).not_to have_content hw_private_goal.title
+    end
+
+    it "hides private goals from other users" do
+      log_in_as(foo_bar)
+      visit user_url(hello_world)
+      expect(page).not_to have_content hw_private_goal.title
+    end
+  end
+end
diff --git a/rails/projects/goal_app_refactor/test/application_system_test_case.rb b/rails/projects/goal_app_refactor/test/application_system_test_case.rb
new file mode 100644
index 0000000..d19212a
--- /dev/null
+++ b/rails/projects/goal_app_refactor/test/application_system_test_case.rb
@@ -0,0 +1,5 @@
+require "test_helper"
+
+class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :chrome, screen_size: [1400, 1400]
+end
diff --git a/rails/projects/goal_app_refactor/test/controllers/.keep b/rails/projects/goal_app_refactor/test/controllers/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/test/fixtures/files/.keep b/rails/projects/goal_app_refactor/test/fixtures/files/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/test/helpers/.keep b/rails/projects/goal_app_refactor/test/helpers/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/test/integration/.keep b/rails/projects/goal_app_refactor/test/integration/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/test/models/.keep b/rails/projects/goal_app_refactor/test/models/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/test/system/.keep b/rails/projects/goal_app_refactor/test/system/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/test/test_helper.rb b/rails/projects/goal_app_refactor/test/test_helper.rb
new file mode 100644
index 0000000..96d5712
--- /dev/null
+++ b/rails/projects/goal_app_refactor/test/test_helper.rb
@@ -0,0 +1,13 @@
+ENV["RAILS_ENV"] ||= "test"
+require_relative "../config/environment"
+require "rails/test_help"
+
+class ActiveSupport::TestCase
+  # Run tests in parallel with specified workers
+  parallelize(workers: :number_of_processors)
+
+  # Setup all fixtures in test/fixtures/*.yml for all tests in alphabetical order.
+  fixtures :all
+
+  # Add more helper methods to be used by all tests here...
+end
\ No newline at end of file
diff --git a/rails/projects/goal_app_refactor/tmp/.keep b/rails/projects/goal_app_refactor/tmp/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/tmp/pids/.keep b/rails/projects/goal_app_refactor/tmp/pids/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/goal_app_refactor/vendor/.keep b/rails/projects/goal_app_refactor/vendor/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/.gitattributes b/rails/projects/helpers_layouts_mailers/.gitattributes
new file mode 100644
index 0000000..34fb547
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/.gitattributes
@@ -0,0 +1,7 @@
+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/.gitignore b/rails/projects/helpers_layouts_mailers/.gitignore
new file mode 100644
index 0000000..4f0da6f
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/.gitignore
@@ -0,0 +1,26 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/.ruby-version b/rails/projects/helpers_layouts_mailers/.ruby-version
new file mode 100644
index 0000000..94ff29c
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/.ruby-version
@@ -0,0 +1 @@
+3.1.1
diff --git a/rails/projects/helpers_layouts_mailers/Gemfile b/rails/projects/helpers_layouts_mailers/Gemfile
new file mode 100644
index 0000000..1cd5cea
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/Gemfile
@@ -0,0 +1,36 @@
+source "https://rubygems.org"
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+ruby "3.1.1"
+
+# Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
+gem "rails", "~> 7.0.2", ">= 7.0.2.2"
+
+# The original asset pipeline for Rails [https://github.com/rails/sprockets-rails]
+gem "sprockets-rails"
+
+# Use postgresql as the database for Active Record
+gem "pg", "~> 1.1"
+
+# Use the Puma web server [https://github.com/puma/puma]
+gem "puma", "~> 5.0"
+
+# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
+gem "tzinfo-data", platforms: %i[ mingw mswin x64_mingw jruby ]
+
+gem "bcrypt"
+
+group :development, :test do
+  # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
+  # gem "debug", platforms: %i[ mri mingw x64_mingw ]
+  gem "byebug", platforms: %i[ mri mingw x64_mingw ]
+end
+
+group :development do
+  # Speed up commands on slow machines / big apps [https://github.com/rails/spring]
+  # gem "spring"
+  gem "annotate"
+  gem "pry-rails"
+  gem "better_errors"
+  gem "binding_of_caller"
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/Gemfile.lock b/rails/projects/helpers_layouts_mailers/Gemfile.lock
new file mode 100644
index 0000000..24c1be0
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/Gemfile.lock
@@ -0,0 +1,198 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailbox (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (>= 2.7.1)
+      net-imap
+      net-pop
+      net-smtp
+    actionmailer (7.0.3)
+      actionpack (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (~> 2.5, >= 2.5.4)
+      net-imap
+      net-pop
+      net-smtp
+      rails-dom-testing (~> 2.0)
+    actionpack (7.0.3)
+      actionview (= 7.0.3)
+      activesupport (= 7.0.3)
+      rack (~> 2.0, >= 2.2.0)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (7.0.3)
+      actionpack (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.6.0)
+      nokogiri (>= 1.8.5)
+    actionview (7.0.3)
+      activesupport (= 7.0.3)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.3.6)
+    activemodel (7.0.3)
+      activesupport (= 7.0.3)
+    activerecord (7.0.3)
+      activemodel (= 7.0.3)
+      activesupport (= 7.0.3)
+    activestorage (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activesupport (= 7.0.3)
+      marcel (~> 1.0)
+      mini_mime (>= 1.1.0)
+    activesupport (7.0.3)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+    addressable (2.8.0)
+      public_suffix (>= 2.0.2, < 5.0)
+    annotate (3.2.0)
+      activerecord (>= 3.2, < 8.0)
+      rake (>= 10.4, < 14.0)
+    bcrypt (3.1.18)
+    better_errors (2.9.1)
+      coderay (>= 1.0.0)
+      erubi (>= 1.0.0)
+      rack (>= 0.9.0)
+    binding_of_caller (1.0.0)
+      debug_inspector (>= 0.0.1)
+    builder (3.2.4)
+    byebug (11.1.3)
+    coderay (1.1.3)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    debug_inspector (1.1.0)
+    digest (3.1.0)
+    erubi (1.10.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
+      concurrent-ruby (~> 1.0)
+    launchy (2.5.0)
+      addressable (~> 2.7)
+    loofah (2.18.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (1.0.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    minitest (5.16.2)
+    net-imap (0.2.3)
+      digest
+      net-protocol
+      strscan
+    net-pop (0.1.1)
+      digest
+      net-protocol
+      timeout
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    pg (1.4.1)
+    pry (0.14.1)
+      coderay (~> 1.1)
+      method_source (~> 1.0)
+    pry-rails (0.3.9)
+      pry (>= 0.10.4)
+    public_suffix (4.0.7)
+    puma (5.6.4)
+      nio4r (~> 2.0)
+    racc (1.6.0)
+    rack (2.2.4)
+    rack-test (2.0.2)
+      rack (>= 1.3)
+    rails (7.0.3)
+      actioncable (= 7.0.3)
+      actionmailbox (= 7.0.3)
+      actionmailer (= 7.0.3)
+      actionpack (= 7.0.3)
+      actiontext (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activemodel (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      bundler (>= 1.15.0)
+      railties (= 7.0.3)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.4.3)
+      loofah (~> 2.3)
+    railties (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      method_source
+      rake (>= 12.2)
+      thor (~> 1.0)
+      zeitwerk (~> 2.5)
+    rake (13.0.6)
+    sprockets (4.1.1)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.4.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      sprockets (>= 3.0.0)
+    strscan (3.0.3)
+    thor (1.2.1)
+    timeout (0.3.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    websocket-driver (0.7.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
+    zeitwerk (2.6.0)
+
+PLATFORMS
+  x86_64-darwin-20
+
+DEPENDENCIES
+  annotate
+  bcrypt
+  better_errors
+  binding_of_caller
+  byebug
+  pg (~> 1.1)
+  pry-rails
+  puma (~> 5.0)
+  rails (~> 7.0.2, >= 7.0.2.2)
+  sprockets-rails
+  tzinfo-data
+
+RUBY VERSION
+   ruby 3.1.1p18
+
+BUNDLED WITH
+   2.3.14
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/README.md b/rails/projects/helpers_layouts_mailers/README.md
new file mode 100644
index 0000000..cfb0907
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/README.md
@@ -0,0 +1,147 @@
+# Helpers, Layouts, And Mailers Homework
+
+For this homework assignment, you will be building on the solution for 99 Cats
+II: Auth. Find the solution in the repo accessed through the `Download Project`
+button at the bottom of this page. Clone the repo, `cd` inside your local copy,
+then run `bundle install` and `bundle exec rails db:setup` to set it up.
+
+## Topic 1: View Helpers
+
+Isn't it pesky to have to rewrite the code for the `form_authenticity_token`
+field over and over? Let's abstract it into a simple helper method that you can
+use across your views.
+
+Open __app/helpers/application_helper.rb__ and write a new method called
+`auth_token`. As a refresher, your auth token code in your views should look
+something like this:
+
+```html
+<input
+  type="hidden"
+  name="authenticity_token"
+  value="<%= form_authenticity_token %>"
+/>
+```
+
+Put this code in your new `auth_token` method, but with a few changes. First,
+you need to wrap the input tag in a string and call `#html_safe` on it.
+Otherwise, your `auth_token` method will output the string literal for your
+input tag. Secondly, now that your input tag is little more than a string in
+Ruby-land, you shouldn't interpolate the actual `form_authenticity_token` using
+erb tags. Instead, just interpolate `form_authenticity_token` using the string
+interpolation syntax you know and love (`#{}`).
+
+Sweet! Looking good? Now go through your app and replace all of the
+`form_authenticity_token` input fields with calls to your snazzy new method,
+`<%= auth_token %>`, to dry up your code and simplify your life.
+
+## Topic 2: Layouts
+
+You've been using layouts in Rails every day without even knowing it! Check
+out your __application.html.erb__ file. In particular, notice the `<%= yield %>`
+tag in the middle of the layout. This will yield in the content for whatever
+page you're on, whether that's the cats index or the new user form.
+
+Now, suppose you wanted to add a footer on your __application.html.erb__ layout.
+You want your footer to display a paragraph describing your site on every page
+of your site. In addition, you want it to display a line describing the
+particular page the user is on. This is a perfect time to use Rails's
+`content_for` method.
+
+First, create a footer section in your __application.html.erb__ at the end of
+the `body` tag and write a short blurb describing your site. Verify that this
+shows up on every page as you navigate around in `localhost`.
+
+Next, add a second `yield` tag to insert the custom footer content within
+the new footer section. It should look something like this:
+
+```erb
+<footer>
+  This is our 99 Cats site. Please feel free to browse!
+
+  <%= yield :footer %>
+</footer>
+```
+
+Now, time to add some page specific content. Go through each of your views, and
+add a line specific to that page. It should look something like this:
+
+```erb
+<p>Other content for the cats index goes here</p>
+
+<% content_for :footer do %>
+  <p>This is the cats index page.</p>
+<% end %>
+```
+
+Finished? Navigate around your site in localhost. Make sure that the main body
+of each page appears in the main `yield` section of the layout and that your
+footer-specific content appears in the footer.
+
+## Topic 3: Action Mailer
+
+1. Activate Action Mailer by uncommenting `require "action_mailer/railtie"` in
+   __config/application.rb__.
+
+2. Create a user mailer to welcome new users to your account. The `rails g
+   mailer User` command will create a new mailer class file in
+   __app/mailers/user_mailer.rb__.
+
+   ```ruby
+   # app/mailers/user_mailer.rb
+
+   class UserMailer < ApplicationMailer
+   end
+   ```
+
+3. Implement a `#welcome_email` method that will email a user from
+   `99catsadmin@appacademy.io`. (You don't actually have an email address stored
+   for the user; for now, just pretend that their username will be an email
+   address.)
+
+   Need a hint? Refer back to the Action Mailer reading.
+
+   ```ruby
+   # app/mailers/user_mailer.rb
+
+   class UserMailer < ApplicationMailer
+     def welcome_email(user)
+       # your code here
+     end
+   end
+   ```
+
+4. Next, write the content for the email welcoming the user to the site. Create
+   a __welcome_email.html.erb__ file in __app/views/user_mailer/__ and fill it
+   in. Inform the user of their successfully created username and provide them
+   with a link to the sign-in page.
+
+   In addition to the __.html.erb__ file, make a text-only version in
+   __welcome_email.txt.erb__. Remember: omitting a text version of your email
+   could cause many filters interpret your email as spam!
+
+5. When a user signs up for your app, send them the welcome email. Where should
+   that code live within your existing `UsersController`? Implement the code.
+
+   Remember, you need a few things. You must call your new `welcome_email`
+   method, which returns a message, and call `deliver_now` on that message to
+   actually send it:
+
+   ```ruby
+   msg = UserMailer.welcome_email(@user)
+   msg.deliver_now
+   ```
+
+6. Test it out! Set up the `letter_opener` gem so that you can try out your code
+   on `localhost:3000`:
+
+   ```ruby
+   # Gemfile
+   gem 'letter_opener', group: :development
+
+   # config/environments/development.rb
+   config.action_mailer.delivery_method = :letter_opener
+   ```
+
+   The sent message should pop up in the browser if all went according to plan.
+   Congrats! You've Action Mailed!
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/Rakefile b/rails/projects/helpers_layouts_mailers/Rakefile
new file mode 100644
index 0000000..d298243
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/Rakefile
@@ -0,0 +1,6 @@
+# Add your own tasks in files placed in lib/tasks ending in .rake,
+# for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
+
+require_relative "config/application"
+
+Rails.application.load_tasks
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/assets/config/manifest.js b/rails/projects/helpers_layouts_mailers/app/assets/config/manifest.js
new file mode 100644
index 0000000..f83f92b
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/assets/config/manifest.js
@@ -0,0 +1,2 @@
+//= link_tree ../images
+//= link_directory ../stylesheets .css
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/assets/images/.keep b/rails/projects/helpers_layouts_mailers/app/assets/images/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/app/assets/stylesheets/application.css b/rails/projects/helpers_layouts_mailers/app/assets/stylesheets/application.css
new file mode 100644
index 0000000..e5faea8
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/assets/stylesheets/application.css
@@ -0,0 +1,168 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS and SCSS file within this directory, lib/assets/stylesheets, or any plugin's
+ * vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS/SCSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree .
+ *= require_self
+ */
+
+ html, body, section, article, h1, h2, p, nav, main, figure {
+   margin: 0;
+   border: 0;
+   padding: 0;
+   font: inherit;
+   text-align: inherit;
+   text-decoration: inherit;
+   color: inherit;
+   background: transparent;
+   font-family: 'Amatic SC', cursive;
+   font-size: 30px;
+ }
+
+nav {
+  width: 100%;
+  background-color: #000066;
+  height: 60px;
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  box-sizing: border-box;
+  padding: 0 20px;
+  color: yellow;
+}
+
+h1 {
+  font-size: 60px;
+  color: yellow;
+}
+
+a {
+  color: yellow;
+}
+
+
+nav a {
+  padding: 0px 10px;
+}
+
+table {
+  background-color: white;
+  margin: auto;
+}
+
+th {
+  background-color: #000066;
+  color: yellow;
+  padding: 10px 20px;
+}
+
+textarea, select, input {
+  font-family: 'Amatic SC', cursive;
+  background-color: inherit;
+  border: 0px;
+  border-bottom: 5px solid yellow;
+  font-size: 30px;
+  margin: 5px 10px;
+}
+
+input[type="submit"]:hover {
+  cursor: pointer;
+}
+
+input[type="submit"] {
+  font-weight: bold;
+}
+
+input:focus, select:focus, textarea:focus {
+  outline: none;
+}
+
+label {
+  font-weight: bold;
+  margin: 15px 0px;
+}
+
+textarea {
+  display: block;
+  margin: auto;
+  width: 300px;
+  background-color: white;
+}
+
+nav form {
+  display: inline;
+}
+
+nav input {
+  color: yellow;
+}
+
+.main-nav {
+  top: 0px;
+  z-index: 100;
+}
+
+.button_to div {
+  display: inline;
+}
+
+
+.jumbotron {
+  height: 500px;
+  width: 100%;
+  background-size: cover;
+  background-image: url("cat_jumbotron.jpg");
+}
+
+.jumbotron h1 {
+  font-size: 150px;
+  color: yellow;
+  position: absolute;
+  bottom: 120px;
+  right: 50px;
+}
+
+.cat-index-holder {
+  margin: 50px auto;
+  width: 920px;
+  background-color: #009999;
+}
+
+.cat-index {
+  width: 100%;
+  display: flex;
+  justify-content: space-around;
+  flex-wrap: wrap;
+}
+
+.cat-index-item {
+  padding: 20px;
+  margin: 20px 0;
+  width: 235px;
+  height: 280px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background-color: #000066;
+}
+
+.page {
+  display: flex;
+  justify-content: space-around;
+}
+
+.centered-box {
+  width: 500px;
+  margin: 50px 0;
+  background-color: #009999;
+  text-align: center;
+  padding: 50px;
+}
diff --git a/rails/projects/helpers_layouts_mailers/app/controllers/application_controller.rb b/rails/projects/helpers_layouts_mailers/app/controllers/application_controller.rb
new file mode 100644
index 0000000..c18276c
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/controllers/application_controller.rb
@@ -0,0 +1,33 @@
+class ApplicationController < ActionController::Base
+  # Expose `current_user` and `logged_in?` methods to the views
+  helper_method :current_user, :logged_in?
+
+  private
+
+  def current_user
+    return nil unless session[:session_token]
+    @current_user ||= User.find_by(session_token: session[:session_token])
+  end
+
+  def logged_in?
+    !!current_user
+  end
+
+  def login!(user)
+    @current_user = user
+    session[:session_token] = user.reset_session_token!
+  end
+
+  def logout!
+    current_user.try(:reset_session_token!)
+    session[:session_token] = nil
+  end
+
+  def require_logged_out
+    redirect_to cats_url if current_user
+  end
+
+  def require_logged_in
+    redirect_to new_session_url unless current_user
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/controllers/cat_rental_requests_controller.rb b/rails/projects/helpers_layouts_mailers/app/controllers/cat_rental_requests_controller.rb
new file mode 100644
index 0000000..b0448ec
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/controllers/cat_rental_requests_controller.rb
@@ -0,0 +1,51 @@
+class CatRentalRequestsController < ApplicationController
+  before_action :require_logged_in, only: %i(new create)
+  before_action :require_cat_ownership, only: %i(approve deny)
+  
+  def approve
+    current_cat_rental_request.approve!
+    redirect_to cat_url(current_cat)
+  end
+
+  def create
+    @rental_request = CatRentalRequest.new(cat_rental_request_params)
+    @rental_request.requester = current_user
+    if @rental_request.save
+      redirect_to cat_url(@rental_request.cat)
+    else
+      flash.now[:errors] = @rental_request.errors.full_messages
+      render :new
+    end
+  end
+
+  def deny
+    current_cat_rental_request.deny!
+    redirect_to cat_url(current_cat)
+  end
+
+  def new
+    @rental_request = CatRentalRequest.new
+    # Grab the cat_id from params if it exists. 
+    # If it doesn't exist, :cat_id will still be nil.
+    @rental_request.cat_id = params[:cat_id] 
+  end
+
+  private
+
+  def current_cat_rental_request
+    @rental_request ||=
+      CatRentalRequest.includes(:cat).find(params[:id])
+  end
+
+  def current_cat
+    current_cat_rental_request.cat
+  end
+
+  def require_cat_ownership
+    redirect_to cat_url(current_cat) unless current_user.owns_cat?(current_cat)
+  end
+
+  def cat_rental_request_params
+    params.require(:cat_rental_request).permit(:cat_id, :end_date, :start_date, :status)
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/controllers/cats_controller.rb b/rails/projects/helpers_layouts_mailers/app/controllers/cats_controller.rb
new file mode 100644
index 0000000..64151e6
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/controllers/cats_controller.rb
@@ -0,0 +1,54 @@
+class CatsController < ApplicationController
+  before_action :require_cat_ownership, only: %i(edit update)
+  before_action :require_logged_in, only: %i(new create)
+
+  def index
+    @cats = Cat.all
+    render :index
+  end
+
+  def show
+    @cat = Cat.find(params[:id])
+    render :show
+  end
+
+  def new
+    @cat = Cat.new
+    render :new
+  end
+
+  def create
+    @cat = Cat.new(cat_params)
+    @cat.owner = current_user
+    if @cat.save
+      redirect_to cat_url(@cat)
+    else
+      flash.now[:errors] = @cat.errors.full_messages
+      render :new
+    end
+  end
+
+  def edit
+    render :edit
+  end
+
+  def update
+    if @cat.update(cat_params)
+      redirect_to cat_url(@cat)
+    else
+      flash.now[:errors] = @cat.errors.full_messages
+      render :edit
+    end
+  end
+
+  private
+
+  def cat_params
+    params.require(:cat).permit(:birth_date, :color, :description, :name, :sex)
+  end
+
+  def require_cat_ownership
+    @cat = current_user&.cats&.find_by(id: params[:id])
+    redirect_to cats_url unless @cat
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/controllers/concerns/.keep b/rails/projects/helpers_layouts_mailers/app/controllers/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/app/controllers/sessions_controller.rb b/rails/projects/helpers_layouts_mailers/app/controllers/sessions_controller.rb
new file mode 100644
index 0000000..20c784e
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/controllers/sessions_controller.rb
@@ -0,0 +1,26 @@
+class SessionsController < ApplicationController
+  before_action :require_logged_out, only: %i(create new)
+
+  def create
+    user = User.find_by_credentials(
+      params[:user][:username],
+      params[:user][:password]
+    )
+
+    if user.nil?
+      flash.now[:errors] = ["Incorrect username and/or password"]
+      render :new
+    else
+      login!(user)
+      redirect_to cats_url
+    end
+  end
+
+  def destroy
+    logout!
+    redirect_to new_session_url
+  end
+
+  def new
+  end
+end
diff --git a/rails/projects/helpers_layouts_mailers/app/controllers/users_controller.rb b/rails/projects/helpers_layouts_mailers/app/controllers/users_controller.rb
new file mode 100644
index 0000000..1cbb591
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/controllers/users_controller.rb
@@ -0,0 +1,24 @@
+class UsersController < ApplicationController
+  before_action :require_logged_out
+
+  def create
+    @user = User.new(user_params)
+    if @user.save
+      login!(@user)
+      redirect_to cats_url
+    else
+      flash.now[:errors] = @user.errors.full_messages
+      render :new
+    end
+  end
+
+  def new
+    @user = User.new
+  end
+
+  private
+
+  def user_params
+    params.require(:user).permit(:password, :username)
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/helpers/application_helper.rb b/rails/projects/helpers_layouts_mailers/app/helpers/application_helper.rb
new file mode 100644
index 0000000..71128bb
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/helpers/application_helper.rb
@@ -0,0 +1,9 @@
+module ApplicationHelper
+  def auth_token
+    "<input
+      type='hidden'
+      name='authenticity_token'
+      value='#{form_authenticity_token}'
+    />".html_safe
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/models/application_record.rb b/rails/projects/helpers_layouts_mailers/app/models/application_record.rb
new file mode 100644
index 0000000..b63caeb
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/models/application_record.rb
@@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+  primary_abstract_class
+end
diff --git a/rails/projects/helpers_layouts_mailers/app/models/cat.rb b/rails/projects/helpers_layouts_mailers/app/models/cat.rb
new file mode 100644
index 0000000..7dcf086
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/models/cat.rb
@@ -0,0 +1,51 @@
+# == Schema Information
+#
+# Table name: cats
+#
+#  id          :bigint           not null, primary key
+#  birth_date  :date             not null
+#  color       :string           not null
+#  name        :string           not null
+#  sex         :string(1)        not null
+#  description :text
+#  created_at  :datetime         not null
+#  updated_at  :datetime         not null
+#  owner_id    :bigint           not null
+#
+require 'action_view'
+
+class Cat < ApplicationRecord
+  include ActionView::Helpers::DateHelper
+
+  # .freeze renders a constant immutable.
+  CAT_COLORS = %w[black white orange brown].freeze
+
+  validates :color, inclusion: CAT_COLORS
+  validates :sex, inclusion: %w[M F]
+  # Note that you don't need to validate `color` or `sex` for presence because
+  # NULL values for those columns will fail the inclusion tests.
+  validates :birth_date, :name, presence: true
+  validate :birth_date_cannot_be_future
+
+  # Remember: `belongs_to` and `has_many` are just methods where the first
+  # argument is the name of the association and the second argument is an
+  # options hash.
+  belongs_to :owner,
+    class_name: 'User'
+
+  has_many :rental_requests,
+    class_name: :CatRentalRequest,
+    dependent: :destroy
+
+  def birth_date_cannot_be_future
+    # Must check that birth_date is present because `>` will crash if run on
+    # `nil`
+    return unless birth_date.present? && birth_date > Date.today
+
+    errors.add(:birth_date, "can't be in the future")
+  end
+
+  def age
+    time_ago_in_words(birth_date)
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/models/cat_rental_request.rb b/rails/projects/helpers_layouts_mailers/app/models/cat_rental_request.rb
new file mode 100644
index 0000000..bd5edc0
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/models/cat_rental_request.rb
@@ -0,0 +1,161 @@
+# == Schema Information
+#
+# Table name: cat_rental_requests
+#
+#  id           :bigint           not null, primary key
+#  cat_id       :bigint           not null
+#  start_date   :date             not null
+#  end_date     :date             not null
+#  status       :string           default("PENDING"), not null
+#  created_at   :datetime         not null
+#  updated_at   :datetime         not null
+#  requester_id :bigint           not null
+#
+class CatRentalRequest < ApplicationRecord
+  # .freeze renders constants immutable
+  STATUS_STATES = %w[APPROVED DENIED PENDING].freeze
+
+  validates :status, inclusion: STATUS_STATES
+  # The `presence` of `status` is guaranteed if it is included in
+  # `STATUS_STATES`; no need to check for it again.
+  validates :end_date, :start_date, presence: true
+  validate :start_must_come_before_end
+  validate :does_not_overlap_approved_request
+
+  belongs_to :cat
+  belongs_to :requester,
+    class_name: :User
+
+  after_initialize :assign_pending_status
+
+  def approve!
+    raise 'not pending' unless self.status == 'PENDING'
+
+    transaction do
+      self.status = 'APPROVED'
+      self.save!
+
+      # When you approve this request, you reject all other overlapping
+      # requests for this cat.
+      overlapping_pending_requests.each do |req|
+        req.update!(status: 'DENIED')
+      end
+    end
+  end
+
+  def approved?
+    self.status == 'APPROVED'
+  end
+
+  def denied?
+    self.status == 'DENIED'
+  end
+
+  def deny!
+    self.status = 'DENIED'
+    self.save!
+  end
+
+  def pending?
+    self.status == 'PENDING'
+  end
+
+  private
+
+  def assign_pending_status
+    self.status ||= 'PENDING'
+  end
+
+  def overlapping_requests
+    # ==========================================================================
+    #
+    # Ranges can overlap in several ways:
+    #
+    #   |-----|       |-----|     |---|
+    #       |-----|   |-----|   |-------|
+    #     (2x)                    (2x)
+    #
+    # ==========================================================================
+    #
+    # However, it is easier to think of the two cases where they do not overlap:
+    #
+    #    [Case 1]
+    #
+    #        A              B
+    #    |-------|      |-------|
+    #    A(s)    A(e)   B(s)    B(e)
+    #
+    # The start point of B comes after the end point of A. Thus: B(s) > A(e)
+    #
+    #
+    #    [Case 2]
+    #
+    #        B              A
+    #    |-------|      |-------|
+    #    B(s)    B(e)   A(s)    A(e)
+    #
+    # The start point of A comes after the end point of B. Thus: A(s) > B(e)
+    #
+    # ==========================================================================
+    #
+    # Taking those two cases, you can say there's no overlap when:
+    #
+    #   B(s) > A(e) || A(s) > B(e)
+    #
+    # ==========================================================================
+    #
+    # You can negate this to get all cases where there must be overlap:
+    #
+    #   !( B(s) > A(e) || A(s) > B(e) )
+    #
+    # In order for overlap to occur, the other range cannot be entirely before
+    # it or entirely after it.
+    #
+    # ==========================================================================
+    #
+    # You could distribute the negation:
+    #
+    #   !( B(s) > A(e) ) && !( A(s) > B(e) )
+    #
+    # And take it even further, making it shorter, but perhaps less intuitive:
+    #
+    #   B(s) <= A(e) && A(s) <= B(e)
+    #
+    # ==========================================================================
+
+    # You want:
+    # 1. A different request
+    # 2. That is for the same cat.
+    # 3. That overlaps.
+
+    CatRentalRequest
+      .where.not(id: self.id)
+      .where(cat_id: cat_id)
+      .where.not('start_date > :end_date OR end_date < :start_date',
+                 start_date: start_date, end_date: end_date)
+  end
+
+  def overlapping_approved_requests
+    overlapping_requests.where('status = \'APPROVED\'')
+  end
+
+  def overlapping_pending_requests
+    overlapping_requests.where('status = \'PENDING\'')
+  end
+
+  def does_not_overlap_approved_request
+    # A denied request doesn't need to be checked. A pending request
+    # should be checked; users shouldn't be able to make requests for
+    # periods during which a cat has already been spoken for.
+    return if self.denied? || overlapping_approved_requests.empty?
+
+    errors.add(:base, 'Request conflicts with existing approved request')
+  end
+
+  def start_must_come_before_end
+    return if start_date < end_date
+
+    errors.add(:start_date, 'must come before end date')
+    errors.add(:end_date, 'must come after start date')
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/models/concerns/.keep b/rails/projects/helpers_layouts_mailers/app/models/concerns/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/app/models/user.rb b/rails/projects/helpers_layouts_mailers/app/models/user.rb
new file mode 100644
index 0000000..de239f5
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/models/user.rb
@@ -0,0 +1,75 @@
+# == Schema Information
+#
+# Table name: users
+#
+#  id              :bigint           not null, primary key
+#  username        :string           not null
+#  password_digest :string           not null
+#  session_token   :string           not null
+#  created_at      :datetime         not null
+#  updated_at      :datetime         not null
+#
+class User < ApplicationRecord
+  validates :username, :session_token, presence: true, uniqueness: true
+  validates :password_digest, presence: true
+  # If a password was set, validate that it meets the requirements.
+  # Note the `allow_nil`.
+  validates :password, length: { minimum: 6, allow_nil: true }
+
+  before_validation :ensure_session_token
+
+  attr_reader :password
+
+  # Remember: `has_many` is just a method where the first argument is the name
+  # of the association and the second argument is an options hash.
+  has_many :cats,
+    foreign_key: :owner_id,
+    dependent: :destroy,
+    inverse_of: :owner
+
+  has_many :cat_rental_requests,
+    foreign_key: :requester_id,
+    dependent: :destroy,
+    inverse_of: :requester
+
+  def self.find_by_credentials(username, password)
+    user = User.find_by(username: username)
+    # `user&.is_password?(password)` is syntactic sugar for
+    # `user && user.is_password?(password)`
+    user&.is_password?(password) ? user : nil
+  end
+
+  def is_password?(password)
+    BCrypt::Password.new(self.password_digest).is_password?(password)
+  end
+
+  def password=(password)
+    @password = password
+    self.password_digest = BCrypt::Password.create(password)
+  end
+
+  def reset_session_token!
+    self.session_token = generate_unique_session_token
+    self.save!
+    self.session_token
+  end
+
+  def owns_cat?(cat)
+    cat.owner == self
+  end
+
+  private
+
+  def generate_unique_session_token
+    # `SecureRandom::urlsafe_base64` does not guarantee uniqueness. Wrapping
+    # this call in a loop ensures that no other user has the generated token.
+    loop do
+      session_token = SecureRandom::urlsafe_base64(16)
+      return session_token unless User.exists?(session_token: session_token)
+    end
+  end
+
+  def ensure_session_token
+    self.session_token ||= generate_unique_session_token
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/cat_rental_requests/new.html.erb b/rails/projects/helpers_layouts_mailers/app/views/cat_rental_requests/new.html.erb
new file mode 100644
index 0000000..29417f8
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/cat_rental_requests/new.html.erb
@@ -0,0 +1,48 @@
+<section class="page"><div class="centered-box">
+  <h1>Create Rental Request</h1>
+
+  <%= render "shared/errors" %>
+
+  <form action="<%= cat_rental_requests_url %>" method="post">
+    <input
+      type="hidden"
+      name="authenticity_token"
+      value="<%= form_authenticity_token %>"
+    >
+
+    <label for="cat_rental_request_cat_id">Cat</label>
+    <select name="cat_rental_request[cat_id]"
+            id="cat_rental_request_cat_id"
+            required>
+      <option selected disabled>--Select Cat--</option>
+      <% Cat.all.each do |cat| %>
+        <% selected = @rental_request.cat_id == cat.id %>
+        <option <%= selected ? "selected" : "" %>
+                value="<%= cat.id %>">
+          <%= cat.name %>
+        </option>
+      <% end %>
+    </select>
+    <br>
+
+    <label for="cat_rental_request_start_date">Start Date</label>
+    <input
+      type="date"
+      name="cat_rental_request[start_date]"
+      value="<%= @rental_request.start_date %>"
+      id="cat_rental_request_start_date"
+      required>
+    <br>
+
+    <label for="cat_rental_request_end_date">End Date</label>
+    <input
+      type="date"
+      name="cat_rental_request[end_date]"
+      value="<%= @rental_request.end_date %>"
+      id="cat_rental_request_end_date"
+      required>
+    <br>
+
+    <input type="submit" value="Submit">
+  </form>
+</div></section>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/cats/_form.html.erb b/rails/projects/helpers_layouts_mailers/app/views/cats/_form.html.erb
new file mode 100644
index 0000000..6d54860
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/cats/_form.html.erb
@@ -0,0 +1,69 @@
+<% action = (cat.persisted? ? cat_url(cat) : cats_url) %>
+<% method = (cat.persisted? ? :PATCH : :POST) %>
+
+<form action="<%= action %>" method="POST">
+  <input type="hidden" name="_method" value="<%= method %>">
+  <input
+    type="hidden"
+    name="authenticity_token"
+    value="<%= form_authenticity_token %>"
+  >
+
+  <label for="cat_name">Name</label>
+  <input
+    type="text"
+    name="cat[name]"
+    id="cat_name"
+    value="<%= cat.name %>"
+  >
+  <br>
+
+  <label for="cat_birth_date">Birth date</label>
+  <input
+    type="date"
+    name="cat[birth_date]"
+    id="cat_birth_date"
+    value="<%= cat.birth_date %>"
+  >
+  <br>
+
+  <label for="cat_color">Color</label>
+  <select name="cat[color]" id="cat_color">
+    <option disabled selected>-- select a color --</option>
+      <% Cat::CAT_COLORS.each do |color| %>
+        <option
+          <%= cat.color == color ? "selected" : "" %>
+          value="<%= color %>">
+          <%= color.upcase %>
+        </option>
+      <% end %>
+  </select>
+  <br>
+
+  <input
+    type="radio"
+    name="cat[sex]"
+    value="M"
+    id="cat_sex_male"
+    <%= cat.sex == "M" ? "checked" : "" %>
+  >
+  <label for="cat_sex_male">Male</label>
+  <input
+    type="radio"
+    name="cat[sex]"
+    value="F"
+    id="cat_sex_female"
+    <%= cat.sex == "F" ? "checked" : "" %>
+  >
+  <label for="cat_sex_female">Female</label>
+  <br>
+
+  <label>
+    Description
+    <textarea name="cat[description]"><%= cat.description %></textarea>
+  </label>
+
+  <br>
+  <% submit_text = (cat.persisted? ? 'Update' : 'Create') + ' cat!' %>
+  <input type="submit" value="<%= submit_text %>">
+</form>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/cats/_req_tr.html.erb b/rails/projects/helpers_layouts_mailers/app/views/cats/_req_tr.html.erb
new file mode 100644
index 0000000..6018e78
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/cats/_req_tr.html.erb
@@ -0,0 +1,29 @@
+<% is_cat_owner = current_user && current_user.owns_cat?(@cat) %>
+
+<tr>
+  <td><%= req.requester.username %></td>
+  <td><%= req.start_date %></td>
+  <td><%= req.end_date %></td>
+  <td>
+    <% if req.pending? && is_cat_owner %>
+      <form action="<%= approve_cat_rental_request_url(req) %>" method="post">
+        <input
+          type="hidden"
+          name="authenticity_token"
+          value="<%= form_authenticity_token %>"
+        >
+        <input type="submit" value="Approve">
+      </form>
+      <form action="<%= deny_cat_rental_request_url(req) %>" method="post">
+        <input
+          type="hidden"
+          name="authenticity_token"
+          value="<%= form_authenticity_token %>"
+        >
+        <input type="submit" value="Deny">
+      </form>
+    <% else %>
+      <%= req.status %>
+    <% end %>
+  </td>
+</tr>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/cats/edit.html.erb b/rails/projects/helpers_layouts_mailers/app/views/cats/edit.html.erb
new file mode 100644
index 0000000..3df7fa1
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/cats/edit.html.erb
@@ -0,0 +1,5 @@
+<section class="page"><div class="centered-box">
+  <h1>Edit My Cat</h1>
+  <%= render 'shared/errors' %>
+  <%= render 'form', cat: @cat %>
+</div></section>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/cats/index.html.erb b/rails/projects/helpers_layouts_mailers/app/views/cats/index.html.erb
new file mode 100644
index 0000000..ea40a5e
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/cats/index.html.erb
@@ -0,0 +1,23 @@
+<section class="cat-index-holder">
+  <nav>
+    <h1>ALL THE CATS IN THE WORLD</h1>
+    <a href="<%= new_cat_url %>">
+      Add Cat
+      <i class="fa fa-plus" aria-hidden="true"></i>
+    </a>
+    <a href="<%= new_cat_rental_request_url %>">
+      Request a Rental
+      <i class="fa fa-plus" aria-hidden="true"></i>
+    </a>
+  </nav>
+  <section class="cat-index">
+    <% @cats.each do |cat| %>
+      <div class="cat-index-item">
+        <div>
+          <img src="http://placekitten.com/g/231/231" >
+          <br /><a href="<%= cat_url(cat) %>">Rent <%= cat.name %></a>
+        </div>
+      </div>
+    <% end %>
+  </section>
+</section>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/cats/new.html.erb b/rails/projects/helpers_layouts_mailers/app/views/cats/new.html.erb
new file mode 100644
index 0000000..dc96069
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/cats/new.html.erb
@@ -0,0 +1,5 @@
+<section class="page"><div class="centered-box">
+  <h1>New Cat</h1>
+  <%= render 'shared/errors' %>
+  <%= render 'form', cat: @cat %>
+</div></section>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/cats/show.html.erb b/rails/projects/helpers_layouts_mailers/app/views/cats/show.html.erb
new file mode 100644
index 0000000..ec0acde
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/cats/show.html.erb
@@ -0,0 +1,52 @@
+<section class="page"><div class="centered-box">
+  <img src="http://placekitten.com/g/300/300" >
+  <h1><%= @cat.name %></h1>
+
+  <table>
+    <tr>
+      <th>Attribute</th>
+      <th>Value</th>
+    </tr>
+    <% [:age, :birth_date, :color, :sex].each do |attr_name| %>
+      <tr>
+        <td><%= attr_name %></td>
+        <td><%= @cat.send(attr_name) %></td>
+      </tr>
+    <% end %>
+    <% if @cat.description.present? %>
+      <tr>
+        <th colspan="2">Description</th>
+      </tr>
+      <tr>
+        <td colspan="2"><%= @cat.description %></td>
+      </tr>
+    <% end %>
+  </table>
+
+  <% if @cat.owner == current_user %>
+    <a href="<%= edit_cat_url(@cat) %>">Edit <%= @cat.name %></a>
+  <% end %>
+
+  <br><br>
+  <h1>Rental Requests</h1>
+  <% if @cat.rental_requests.empty? %>
+    <p><%= @cat.name %> has no rental requests.</p>
+  <% else %>
+    <table>
+      <tr>
+        <th>User</th>
+        <th>Start Date</th>
+        <th>End Date</th>
+        <th>Status</th>
+      </tr>
+      <% @cat.rental_requests.includes(:requester).order('start_date').each do |req| %>
+        <%= render 'req_tr', req: req %>
+      <% end %>
+    </table>
+  <% end %>
+  <% if logged_in? %>
+    <a href="<%= new_cat_cat_rental_request_url(@cat) %>">
+      Request a Rental
+    </a>  
+  <% end %>
+</div></section>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/layouts/application.html.erb b/rails/projects/helpers_layouts_mailers/app/views/layouts/application.html.erb
new file mode 100644
index 0000000..9595a39
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/layouts/application.html.erb
@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>99 Cats</title>
+    <link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" integrity="sha384-wvfXpqpZZVQGK6TAh5PVlGOfQNHSoD2xbE+QkPxCAFlNEevoEH3Sl0sibVcOQVnN" crossorigin="anonymous">
+    <link href="https://fonts.googleapis.com/css?family=Amatic+SC:400,700" rel="stylesheet">
+    <meta name="viewport" content="width=device-width,initial-scale=1">
+    <%= csrf_meta_tags %>
+    <%= csp_meta_tag %>
+
+    <%= stylesheet_link_tag "application" %>
+  </head>
+
+  <body>
+    <nav class="main-nav">
+      <h1><a href="<%= cats_url %>">99 Cats</a></h1>
+      <div>
+        <% if current_user.nil? %>
+          <a href="<%= new_session_url %>">Sign in</a>
+          <a href="<%= new_user_url %>">Sign up</a>
+        <% else %>
+          <%= current_user.username %>
+          <form action="<%= session_url %>" method="post">
+            <input
+              type="hidden"
+              name="authenticity_token"
+              value="<%= form_authenticity_token %>"
+            >
+            <input type="hidden" name="_method" value="delete">
+            <input type="submit" value="Logout">
+          </form>
+        <% end %>
+      </div>
+    </nav>
+    <main>
+      <%= yield %>
+    </main>
+  </body>
+</html>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/sessions/new.html.erb b/rails/projects/helpers_layouts_mailers/app/views/sessions/new.html.erb
new file mode 100644
index 0000000..aa7dc8a
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/sessions/new.html.erb
@@ -0,0 +1,23 @@
+<section class="page"><div class="centered-box">
+    <h1>Sign in</h1>
+
+      <%= render "shared/errors" %>
+
+    <form action="<%= session_url %>" method="post">
+      <input
+        type="hidden"
+        name="authenticity_token"
+        value="<%= form_authenticity_token %>"
+      >
+
+      <label for="user_username">Username: </label>
+      <input type="text" name="user[username]" id="user_username">
+      <br>
+
+      <label for="user_password">Password: </label>
+      <input type="password" name="user[password]" id="user_password">
+      <br>
+
+      <input type="submit" value="Sign in">
+    </form>
+</div></section>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/app/views/shared/_errors.html.erb b/rails/projects/helpers_layouts_mailers/app/views/shared/_errors.html.erb
new file mode 100644
index 0000000..71eb920
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/shared/_errors.html.erb
@@ -0,0 +1,7 @@
+<% if flash[:errors] %>
+  <ul>
+  <% flash[:errors].each do |error| %>
+    <li><%= error %></li>
+  <% end %>
+  </ul>
+<% end %>
diff --git a/rails/projects/helpers_layouts_mailers/app/views/users/new.html.erb b/rails/projects/helpers_layouts_mailers/app/views/users/new.html.erb
new file mode 100644
index 0000000..25ec4e5
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/app/views/users/new.html.erb
@@ -0,0 +1,31 @@
+<section class="page">
+  <div class="centered-box">
+    <h1>New User</h1>
+
+    <%= render 'shared/errors' %>
+
+    <form action="<%= users_url %>" method="post">
+      <input
+        type="hidden"
+        name="authenticity_token"
+        value="<%= form_authenticity_token %>"
+      >
+
+      <label for="user_username">Username: </label>
+      <input type="text"
+        name="user[username]"
+        id="user_username"
+        value="<%= @user.username %>">
+      <br>
+
+      <label for="user_password">Password: </label>
+      <input type="password"
+        name="user[password]"
+        id="user_password"
+        value="<%= @user.password %>">
+      <br>
+
+      <input type="submit" value="Sign up!">
+    </form>
+  </div>
+</section>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/bin/bundle b/rails/projects/helpers_layouts_mailers/bin/bundle
new file mode 100644
index 0000000..15f37e3
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/bin/bundle
@@ -0,0 +1,114 @@
+#!/usr/bin/env ruby
+# frozen_string_literal: true
+
+#
+# This file was generated by Bundler.
+#
+# The application 'bundle' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require "rubygems"
+
+m = Module.new do
+  module_function
+
+  def invoked_as_script?
+    File.expand_path($0) == File.expand_path(__FILE__)
+  end
+
+  def env_var_version
+    ENV["BUNDLER_VERSION"]
+  end
+
+  def cli_arg_version
+    return unless invoked_as_script? # don't want to hijack other binstubs
+    return unless "update".start_with?(ARGV.first || " ") # must be running `bundle update`
+    bundler_version = nil
+    update_index = nil
+    ARGV.each_with_index do |a, i|
+      if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
+        bundler_version = a
+      end
+      next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
+      bundler_version = $1
+      update_index = i
+    end
+    bundler_version
+  end
+
+  def gemfile
+    gemfile = ENV["BUNDLE_GEMFILE"]
+    return gemfile if gemfile && !gemfile.empty?
+
+    File.expand_path("../../Gemfile", __FILE__)
+  end
+
+  def lockfile
+    lockfile =
+      case File.basename(gemfile)
+      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
+      else "#{gemfile}.lock"
+      end
+    File.expand_path(lockfile)
+  end
+
+  def lockfile_version
+    return unless File.file?(lockfile)
+    lockfile_contents = File.read(lockfile)
+    return unless lockfile_contents =~ /\n\nBUNDLED WITH\n\s{2,}(#{Gem::Version::VERSION_PATTERN})\n/
+    Regexp.last_match(1)
+  end
+
+  def bundler_requirement
+    @bundler_requirement ||=
+      env_var_version || cli_arg_version ||
+        bundler_requirement_for(lockfile_version)
+  end
+
+  def bundler_requirement_for(version)
+    return "#{Gem::Requirement.default}.a" unless version
+
+    bundler_gem_version = Gem::Version.new(version)
+
+    requirement = bundler_gem_version.approximate_recommendation
+
+    return requirement unless Gem.rubygems_version < Gem::Version.new("2.7.0")
+
+    requirement += ".a" if bundler_gem_version.prerelease?
+
+    requirement
+  end
+
+  def load_bundler!
+    ENV["BUNDLE_GEMFILE"] ||= gemfile
+
+    activate_bundler
+  end
+
+  def activate_bundler
+    gem_error = activation_error_handling do
+      gem "bundler", bundler_requirement
+    end
+    return if gem_error.nil?
+    require_error = activation_error_handling do
+      require "bundler/version"
+    end
+    return if require_error.nil? && Gem::Requirement.new(bundler_requirement).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+    warn "Activating bundler (#{bundler_requirement}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_requirement}'`"
+    exit 42
+  end
+
+  def activation_error_handling
+    yield
+    nil
+  rescue StandardError, LoadError => e
+    e
+  end
+end
+
+m.load_bundler!
+
+if m.invoked_as_script?
+  load Gem.bin_path("bundler", "bundle")
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/bin/rails b/rails/projects/helpers_layouts_mailers/bin/rails
new file mode 100644
index 0000000..fa3c01a
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/bin/rails
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+APP_PATH = File.expand_path("../config/application", __dir__)
+require_relative "../config/boot"
+require "rails/commands"
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/bin/rake b/rails/projects/helpers_layouts_mailers/bin/rake
new file mode 100644
index 0000000..19d605d
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/bin/rake
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+require_relative "../config/boot"
+require "rake"
+Rake.application.run
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/bin/setup b/rails/projects/helpers_layouts_mailers/bin/setup
new file mode 100644
index 0000000..9bd670f
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/bin/setup
@@ -0,0 +1,33 @@
+#!/usr/bin/env ruby
+require "fileutils"
+
+# path to your application root.
+APP_ROOT = File.expand_path("..", __dir__)
+
+def system!(*args)
+  system(*args) || abort("\n== Command #{args} failed ==")
+end
+
+FileUtils.chdir APP_ROOT do
+  # This script is a way to set up or update your development environment automatically.
+  # This script is idempotent, so that you can run it at any time and get an expectable outcome.
+  # Add necessary setup steps to this file.
+
+  puts "== Installing dependencies =="
+  system! "gem install bundler --conservative"
+  system("bundle check") || system!("bundle install")
+
+  # puts "\n== Copying sample files =="
+  # unless File.exist?("config/database.yml")
+  #   FileUtils.cp "config/database.yml.sample", "config/database.yml"
+  # end
+
+  puts "\n== Preparing database =="
+  system! "bin/rails db:prepare"
+
+  puts "\n== Removing old logs and tempfiles =="
+  system! "bin/rails log:clear tmp:clear"
+
+  puts "\n== Restarting application server =="
+  system! "bin/rails restart"
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config.ru b/rails/projects/helpers_layouts_mailers/config.ru
new file mode 100644
index 0000000..38cc27a
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config.ru
@@ -0,0 +1,6 @@
+# This file is used by Rack-based servers to start the application.
+
+require_relative "config/environment"
+
+run Rails.application
+Rails.application.load_server
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/application.rb b/rails/projects/helpers_layouts_mailers/config/application.rb
new file mode 100644
index 0000000..22b7aac
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/application.rb
@@ -0,0 +1,38 @@
+require_relative "boot"
+
+require "rails"
+# Pick the frameworks you want:
+require "active_model/railtie"
+# require "active_job/railtie"
+require "active_record/railtie"
+# require "active_storage/engine"
+require "action_controller/railtie"
+require "action_mailer/railtie"
+# require "action_mailbox/engine"
+# require "action_text/engine"
+require "action_view/railtie"
+# require "action_cable/engine"
+# require "rails/test_unit/railtie"
+
+# Require the gems listed in Gemfile, including any gems
+# you've limited to :test, :development, or :production.
+Bundler.require(*Rails.groups)
+
+module NinetyNineCats2LongPractice
+  class Application < Rails::Application
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults 7.0
+    
+    config.action_controller.default_protect_from_forgery = false
+    # Configuration for the application, engines, and railties goes here.
+    #
+    # These settings can be overridden in specific environments using the files
+    # in config/environments, which are processed later.
+    #
+    # config.time_zone = "Central Time (US & Canada)"
+    # config.eager_load_paths << Rails.root.join("extras")
+
+    # Don't generate system test files.
+    config.generators.system_tests = nil
+  end
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/boot.rb b/rails/projects/helpers_layouts_mailers/config/boot.rb
new file mode 100644
index 0000000..2820116
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/boot.rb
@@ -0,0 +1,3 @@
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+
+require "bundler/setup" # Set up gems listed in the Gemfile.
diff --git a/rails/projects/helpers_layouts_mailers/config/credentials.yml.enc b/rails/projects/helpers_layouts_mailers/config/credentials.yml.enc
new file mode 100644
index 0000000..50395e9
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/credentials.yml.enc
@@ -0,0 +1 @@
+fO7L3PuH/eShQ0tYDhR0SutQiCF2sBx4ZZnspFWAd+OHOSo0bAo88xAhOMJBb4xmltZ6ZRnsddCwc0XQAHn7B6vphQRpGyrxlr6sEvATr3SbmQL6gtYHn353WtUe+swxTRMJ4Uqp2AYtI9fI4WUdAJzA+7UOwSipabDTQKVnpbzlNOgOkIfYGAQ/y1wq5WkRmUrUyOiUz/Qh6Tgd8v4mT9Fcwd9uj7uzmkNC9405KUuS1GEiwnH5Zw7UPGI7VcrQ2sDpmUSYjciZo/eXVOmLQ3lVlJgj7my5FuAEudohh2Vzi2pIc1zP3JJj/NPywzEXfJVP+EqVyZsPAr9JbFK4FPKDxgG2UFmHaSo7nzWzh4XVtLMokZZdifYNTjSOvkc2VQVHQ+nN/zdKt+F/qmUlA6G3mYT/DTmpFz0z--uGSYIi1SQxIBvTVO--iJrSV/vzB/VjM2MMbTpwxQ==
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/database.yml b/rails/projects/helpers_layouts_mailers/config/database.yml
new file mode 100644
index 0000000..2a43b14
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/database.yml
@@ -0,0 +1,86 @@
+# PostgreSQL. Versions 9.3 and up are supported.
+#
+# Install the pg driver:
+#   gem install pg
+# On macOS with Homebrew:
+#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
+# On macOS with MacPorts:
+#   gem install pg -- --with-pg-config=/opt/local/lib/postgresql84/bin/pg_config
+# On Windows:
+#   gem install pg
+#       Choose the win32 build.
+#       Install PostgreSQL and put its /bin directory on your path.
+#
+# Configure Using Gemfile
+# gem "pg"
+#
+default: &default
+  adapter: postgresql
+  encoding: unicode
+  # For details on connection pooling, see Rails configuration guide
+  # https://guides.rubyonrails.org/configuring.html#database-pooling
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+
+development:
+  <<: *default
+  database: ninety_nine_cats2_long_practice_development
+
+  # The specified database role being used to connect to postgres.
+  # To create additional roles in postgres see `$ createuser --help`.
+  # When left blank, postgres will use the default role. This is
+  # the same name as the operating system user running Rails.
+  #username: ninety_nine_cats2_long_practice
+
+  # The password associated with the postgres role (username).
+  #password:
+
+  # Connect on a TCP socket. Omitted by default since the client uses a
+  # domain socket that doesn't need configuration. Windows does not have
+  # domain sockets, so uncomment these lines.
+  #host: localhost
+
+  # The TCP port the server listens on. Defaults to 5432.
+  # If your server runs on a different port number, change accordingly.
+  #port: 5432
+
+  # Schema search path. The server defaults to $user,public
+  #schema_search_path: myapp,sharedapp,public
+
+  # Minimum log levels, in increasing order:
+  #   debug5, debug4, debug3, debug2, debug1,
+  #   log, notice, warning, error, fatal, and panic
+  # Defaults to warning.
+  #min_messages: notice
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: ninety_nine_cats2_long_practice_test
+
+# As with config/credentials.yml, you never want to store sensitive information,
+# like your database password, in your source code. If your source code is
+# ever seen by anyone, they now have access to your database.
+#
+# Instead, provide the password or a full connection URL as an environment
+# variable when you boot the app. For example:
+#
+#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
+#
+# If the connection URL is provided in the special DATABASE_URL environment
+# variable, Rails will automatically merge its configuration values on top of
+# the values provided in this file. Alternatively, you can specify a connection
+# URL environment variable explicitly:
+#
+#   production:
+#     url: <%= ENV["MY_APP_DATABASE_URL"] %>
+#
+# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
+# for a full overview on how database connection configuration can be specified.
+#
+production:
+  <<: *default
+  database: ninety_nine_cats2_long_practice_production
+  username: ninety_nine_cats2_long_practice
+  password: <%= ENV["NINETY_NINE_CATS2_LONG_PRACTICE_DATABASE_PASSWORD"] %>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/environment.rb b/rails/projects/helpers_layouts_mailers/config/environment.rb
new file mode 100644
index 0000000..445c788
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/environment.rb
@@ -0,0 +1,5 @@
+# Load the Rails application.
+require_relative "application"
+
+# Initialize the Rails application.
+Rails.application.initialize!
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/environments/development.rb b/rails/projects/helpers_layouts_mailers/config/environments/development.rb
new file mode 100644
index 0000000..851adc5
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/environments/development.rb
@@ -0,0 +1,62 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # In the development environment your application's code is reloaded any time
+  # it changes. This slows down response time but is perfect for development
+  # since you don't have to restart the web server when you make code changes.
+  config.cache_classes = false
+
+  # Do not eager load code on boot.
+  config.eager_load = false
+
+  # Show full error reports.
+  config.consider_all_requests_local = true
+
+  # Enable server timing
+  config.server_timing = true
+
+  # Enable/disable caching. By default caching is disabled.
+  # Run rails dev:cache to toggle caching.
+  if Rails.root.join("tmp/caching-dev.txt").exist?
+    config.action_controller.perform_caching = true
+    config.action_controller.enable_fragment_cache_logging = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      "Cache-Control" => "public, max-age=#{2.days.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
+
+  # Print deprecation notices to the Rails logger.
+  config.active_support.deprecation = :log
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raise an error on page load if there are pending migrations.
+  config.active_record.migration_error = :page_load
+
+  # Highlight code that triggered database queries in logs.
+  config.active_record.verbose_query_logs = true
+
+  # Suppress logger output for asset requests.
+  config.assets.quiet = true
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+
+  # Uncomment if you wish to allow Action Cable access from any origin.
+  # config.action_cable.disable_request_forgery_protection = true
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/environments/production.rb b/rails/projects/helpers_layouts_mailers/config/environments/production.rb
new file mode 100644
index 0000000..6aee001
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/environments/production.rb
@@ -0,0 +1,75 @@
+require "active_support/core_ext/integer/time"
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Code is not reloaded between requests.
+  config.cache_classes = true
+
+  # Eager load code on boot. This eager loads most of Rails and
+  # your application in memory, allowing both threaded web servers
+  # and those relying on copy on write to perform better.
+  # Rake tasks automatically ignore this option for performance.
+  config.eager_load = true
+
+  # Full error reports are disabled and caching is turned on.
+  config.consider_all_requests_local       = false
+  config.action_controller.perform_caching = true
+
+  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  # config.require_master_key = true
+
+  # Disable serving static files from the `/public` folder by default since
+  # Apache or NGINX already handles this.
+  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
+
+  # Compress CSS using a preprocessor.
+  # config.assets.css_compressor = :sass
+
+  # Do not fallback to assets pipeline if a precompiled asset is missed.
+  config.assets.compile = false
+
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.asset_host = "http://assets.example.com"
+
+  # Specifies the header that your server uses for sending files.
+  # config.action_dispatch.x_sendfile_header = "X-Sendfile" # for Apache
+  # config.action_dispatch.x_sendfile_header = "X-Accel-Redirect" # for NGINX
+
+  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
+  # config.force_ssl = true
+
+  # Include generic and useful information about system operation, but avoid logging too much
+  # information to avoid inadvertent exposure of personally identifiable information (PII).
+  config.log_level = :info
+
+  # Prepend all log lines with the following tags.
+  config.log_tags = [ :request_id ]
+
+  # Use a different cache store in production.
+  # config.cache_store = :mem_cache_store
+
+  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
+  # the I18n.default_locale when a translation cannot be found).
+  config.i18n.fallbacks = true
+
+  # Don't log any deprecations.
+  config.active_support.report_deprecations = false
+
+  # Use default logging formatter so that PID and timestamp are not suppressed.
+  config.log_formatter = ::Logger::Formatter.new
+
+  # Use a different logger for distributed setups.
+  # require "syslog/logger"
+  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
+
+  if ENV["RAILS_LOG_TO_STDOUT"].present?
+    logger           = ActiveSupport::Logger.new(STDOUT)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/environments/test.rb b/rails/projects/helpers_layouts_mailers/config/environments/test.rb
new file mode 100644
index 0000000..da62dfc
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/environments/test.rb
@@ -0,0 +1,50 @@
+require "active_support/core_ext/integer/time"
+
+# The test environment is used exclusively to run your application's
+# test suite. You never need to work with it otherwise. Remember that
+# your test database is "scratch space" for the test suite and is wiped
+# and recreated between test runs. Don't rely on the data there!
+
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Turn false under Spring and add config.action_view.cache_template_loading = true.
+  config.cache_classes = true
+
+  # Eager loading loads your whole application. When running a single test locally,
+  # this probably isn't necessary. It's a good idea to do in a continuous integration
+  # system, or in some way before deploying your code.
+  config.eager_load = ENV["CI"].present?
+
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = {
+    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
+  }
+
+  # Show full error reports and disable caching.
+  config.consider_all_requests_local       = true
+  config.action_controller.perform_caching = false
+  config.cache_store = :null_store
+
+  # Raise exceptions instead of rendering exception templates.
+  config.action_dispatch.show_exceptions = false
+
+  # Disable request forgery protection in test environment.
+  config.action_controller.allow_forgery_protection = false
+
+  # Print deprecation notices to the stderr.
+  config.active_support.deprecation = :stderr
+
+  # Raise exceptions for disallowed deprecations.
+  config.active_support.disallowed_deprecation = :raise
+
+  # Tell Active Support which deprecation messages to disallow.
+  config.active_support.disallowed_deprecation_warnings = []
+
+  # Raises error for missing translations.
+  # config.i18n.raise_on_missing_translations = true
+
+  # Annotate rendered view with file names.
+  # config.action_view.annotate_rendered_view_with_filenames = true
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/initializers/assets.rb b/rails/projects/helpers_layouts_mailers/config/initializers/assets.rb
new file mode 100644
index 0000000..bd8332f
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/initializers/assets.rb
@@ -0,0 +1,12 @@
+# Be sure to restart your server when you modify this file.
+
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = "1.0"
+
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/initializers/content_security_policy.rb b/rails/projects/helpers_layouts_mailers/config/initializers/content_security_policy.rb
new file mode 100644
index 0000000..d9b954b
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/initializers/content_security_policy.rb
@@ -0,0 +1,26 @@
+# Be sure to restart your server when you modify this file.
+
+# Define an application-wide content security policy
+# For further information see the following documentation
+# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
+
+# Rails.application.configure do
+#   config.content_security_policy do |policy|
+#     policy.default_src :self, :https
+#     policy.font_src    :self, :https, :data
+#     policy.img_src     :self, :https, :data
+#     policy.object_src  :none
+#     policy.script_src  :self, :https
+#     policy.style_src   :self, :https
+#     # Specify URI for violation reports
+#     # policy.report_uri "/csp-violation-report-endpoint"
+#   end
+#
+#   # Generate session nonces for permitted importmap and inline scripts
+#   config.content_security_policy_nonce_generator = ->(request) { request.session.id.to_s }
+#   config.content_security_policy_nonce_directives = %w(script-src)
+#
+#   # Report CSP violations to a specified URI. See:
+#   # https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy-Report-Only
+#   # config.content_security_policy_report_only = true
+# end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/initializers/filter_parameter_logging.rb b/rails/projects/helpers_layouts_mailers/config/initializers/filter_parameter_logging.rb
new file mode 100644
index 0000000..b4db5f6
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/initializers/filter_parameter_logging.rb
@@ -0,0 +1,8 @@
+# Be sure to restart your server when you modify this file.
+
+# Configure parameters to be filtered from the log file. Use this to limit dissemination of
+# sensitive information. See the ActiveSupport::ParameterFilter documentation for supported
+# notations and behaviors.
+Rails.application.config.filter_parameters += [
+  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
+]
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/initializers/inflections.rb b/rails/projects/helpers_layouts_mailers/config/initializers/inflections.rb
new file mode 100644
index 0000000..df431d7
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/initializers/inflections.rb
@@ -0,0 +1,16 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new inflection rules using the following format. Inflections
+# are locale specific, and you may define rules for as many different
+# locales as you wish. All of these examples are active by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.plural /^(ox)$/i, "\\1en"
+#   inflect.singular /^(ox)en/i, "\\1"
+#   inflect.irregular "person", "people"
+#   inflect.uncountable %w( fish sheep )
+# end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym "RESTful"
+# end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/initializers/permissions_policy.rb b/rails/projects/helpers_layouts_mailers/config/initializers/permissions_policy.rb
new file mode 100644
index 0000000..dd30019
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/initializers/permissions_policy.rb
@@ -0,0 +1,11 @@
+# Define an application-wide HTTP permissions policy. For further
+# information see https://developers.google.com/web/updates/2018/06/feature-policy
+#
+# Rails.application.config.permissions_policy do |f|
+#   f.camera      :none
+#   f.gyroscope   :none
+#   f.microphone  :none
+#   f.usb         :none
+#   f.fullscreen  :self
+#   f.payment     :self, "https://secure.example.com"
+# end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/locales/en.yml b/rails/projects/helpers_layouts_mailers/config/locales/en.yml
new file mode 100644
index 0000000..30c9973
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/locales/en.yml
@@ -0,0 +1,33 @@
+# Files in the config/locales directory are used for internationalization
+# and are automatically loaded by Rails. If you want to use locales other
+# than English, add the necessary files in this directory.
+#
+# To use the locales, use `I18n.t`:
+#
+#     I18n.t "hello"
+#
+# In views, this is aliased to just `t`:
+#
+#     <%= t("hello") %>
+#
+# To use a different locale, set it with `I18n.locale`:
+#
+#     I18n.locale = :es
+#
+# This would use the information in config/locales/es.yml.
+#
+# The following keys must be escaped otherwise they will not be retrieved by
+# the default I18n backend:
+#
+# true, false, on, off, yes, no
+#
+# Instead, surround them with single quotes.
+#
+# en:
+#   "true": "foo"
+#
+# To learn more, please read the Rails Internationalization guide
+# available at https://guides.rubyonrails.org/i18n.html.
+
+en:
+  hello: "Hello world"
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/puma.rb b/rails/projects/helpers_layouts_mailers/config/puma.rb
new file mode 100644
index 0000000..411b18d
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/puma.rb
@@ -0,0 +1,43 @@
+# Puma can serve each request in a thread from an internal thread pool.
+# The `threads` method setting takes two numbers: a minimum and maximum.
+# Any libraries that use thread pools should be configured to match
+# the maximum value specified for Puma. Default is set to 5 threads for minimum
+# and maximum; this matches the default thread size of Active Record.
+#
+max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
+min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count }
+threads min_threads_count, max_threads_count
+
+# Specifies the `worker_timeout` threshold that Puma will use to wait before
+# terminating a worker in development environments.
+#
+worker_timeout 3600 if ENV.fetch("RAILS_ENV", "development") == "development"
+
+# Specifies the `port` that Puma will listen on to receive requests; default is 3000.
+#
+port ENV.fetch("PORT") { 3000 }
+
+# Specifies the `environment` that Puma will run in.
+#
+environment ENV.fetch("RAILS_ENV") { "development" }
+
+# Specifies the `pidfile` that Puma will use.
+pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
+
+# Specifies the number of `workers` to boot in clustered mode.
+# Workers are forked web server processes. If using threads and workers together
+# the concurrency of the application would be max `threads` * `workers`.
+# Workers do not work on JRuby or Windows (both of which do not support
+# processes).
+#
+# workers ENV.fetch("WEB_CONCURRENCY") { 2 }
+
+# Use the `preload_app!` method when specifying a `workers` number.
+# This directive tells Puma to first boot the application and load code
+# before forking the application. This takes advantage of Copy On Write
+# process behavior so workers use less memory.
+#
+# preload_app!
+
+# Allow puma to be restarted by `bin/rails restart` command.
+plugin :tmp_restart
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/config/routes.rb b/rails/projects/helpers_layouts_mailers/config/routes.rb
new file mode 100644
index 0000000..f12c19f
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/config/routes.rb
@@ -0,0 +1,19 @@
+Rails.application.routes.draw do
+  # Define your application routes per the DSL in https://guides.rubyonrails.org/routing.html
+
+  # Defines the root path route ("/")
+  # root "articles#index"
+  root "cats#index"
+
+  resources :cats, except: :destroy do
+    resources :cat_rental_requests, only: [:new]
+  end
+  resources :cat_rental_requests, only: [:new, :create] do
+    member do
+      post :approve
+      post :deny
+    end
+  end
+  resource :session, only: [:new, :create, :destroy]
+  resources :users, only: [:new, :create]
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/db/migrate/20220301202033_create_cats.rb b/rails/projects/helpers_layouts_mailers/db/migrate/20220301202033_create_cats.rb
new file mode 100644
index 0000000..d89b77d
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/db/migrate/20220301202033_create_cats.rb
@@ -0,0 +1,13 @@
+class CreateCats < ActiveRecord::Migration[7.0]
+  def change
+    create_table :cats do |t|
+      t.date :birth_date, null: false
+      t.string :color, null: false
+      t.string :name, null: false
+      t.string :sex, limit: 1, null: false
+      t.text :description
+
+      t.timestamps
+    end
+  end
+end
diff --git a/rails/projects/helpers_layouts_mailers/db/migrate/20220302053135_create_cat_rental_requests.rb b/rails/projects/helpers_layouts_mailers/db/migrate/20220302053135_create_cat_rental_requests.rb
new file mode 100644
index 0000000..cbed70b
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/db/migrate/20220302053135_create_cat_rental_requests.rb
@@ -0,0 +1,12 @@
+class CreateCatRentalRequests < ActiveRecord::Migration[7.0]
+  def change
+    create_table :cat_rental_requests do |t|
+      t.references :cat, null: false, foreign_key: true
+      t.date :start_date, null: false
+      t.date :end_date, null: false
+      t.string :status, null: false, default: 'PENDING'
+
+      t.timestamps
+    end
+  end
+end
diff --git a/rails/projects/helpers_layouts_mailers/db/migrate/20220610145144_create_users.rb b/rails/projects/helpers_layouts_mailers/db/migrate/20220610145144_create_users.rb
new file mode 100644
index 0000000..b1da12c
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/db/migrate/20220610145144_create_users.rb
@@ -0,0 +1,13 @@
+class CreateUsers < ActiveRecord::Migration[7.0]
+  def change
+    create_table :users do |t|
+      t.string :username, null: false
+      t.string :password_digest, null: false
+      t.string :session_token, null: false
+
+      t.timestamps
+    end
+    add_index :users, :username, unique: true
+    add_index :users, :session_token, unique: true
+  end
+end
diff --git a/rails/projects/helpers_layouts_mailers/db/migrate/20220610214850_add_owner_to_cats.rb b/rails/projects/helpers_layouts_mailers/db/migrate/20220610214850_add_owner_to_cats.rb
new file mode 100644
index 0000000..0e0991b
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/db/migrate/20220610214850_add_owner_to_cats.rb
@@ -0,0 +1,5 @@
+class AddOwnerToCats < ActiveRecord::Migration[7.0]
+  def change
+    add_reference :cats, :owner, null: false, foreign_key: { to_table: :users }
+  end
+end
diff --git a/rails/projects/helpers_layouts_mailers/db/migrate/20220618214048_add_requester_to_cat_rental_requests.rb b/rails/projects/helpers_layouts_mailers/db/migrate/20220618214048_add_requester_to_cat_rental_requests.rb
new file mode 100644
index 0000000..88033ff
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/db/migrate/20220618214048_add_requester_to_cat_rental_requests.rb
@@ -0,0 +1,5 @@
+class AddRequesterToCatRentalRequests < ActiveRecord::Migration[7.0]
+  def change
+    add_reference :cat_rental_requests, :requester, null: false, foreign_key: { to_table: :users }
+  end
+end
diff --git a/rails/projects/helpers_layouts_mailers/db/schema.rb b/rails/projects/helpers_layouts_mailers/db/schema.rb
new file mode 100644
index 0000000..d6840a6
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/db/schema.rb
@@ -0,0 +1,54 @@
+# This file is auto-generated from the current state of the database. Instead
+# of editing this file, please use the migrations feature of Active Record to
+# incrementally modify your database, and then regenerate this schema definition.
+#
+# This file is the source Rails uses to define your schema when running `bin/rails
+# db:schema:load`. When creating a new database, `bin/rails db:schema:load` tends to
+# be faster and is potentially less error prone than running all of your
+# migrations from scratch. Old migrations may fail to apply correctly if those
+# migrations use external dependencies or application code.
+#
+# It's strongly recommended that you check this file into your version control system.
+
+ActiveRecord::Schema[7.0].define(version: 2022_06_18_214048) do
+  # These are extensions that must be enabled in order to support this database
+  enable_extension "plpgsql"
+
+  create_table "cat_rental_requests", force: :cascade do |t|
+    t.bigint "cat_id", null: false
+    t.date "start_date", null: false
+    t.date "end_date", null: false
+    t.string "status", default: "PENDING", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.bigint "requester_id", null: false
+    t.index ["cat_id"], name: "index_cat_rental_requests_on_cat_id"
+    t.index ["requester_id"], name: "index_cat_rental_requests_on_requester_id"
+  end
+
+  create_table "cats", force: :cascade do |t|
+    t.date "birth_date", null: false
+    t.string "color", null: false
+    t.string "name", null: false
+    t.string "sex", limit: 1, null: false
+    t.text "description"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.bigint "owner_id", null: false
+    t.index ["owner_id"], name: "index_cats_on_owner_id"
+  end
+
+  create_table "users", force: :cascade do |t|
+    t.string "username", null: false
+    t.string "password_digest", null: false
+    t.string "session_token", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["session_token"], name: "index_users_on_session_token", unique: true
+    t.index ["username"], name: "index_users_on_username", unique: true
+  end
+
+  add_foreign_key "cat_rental_requests", "cats"
+  add_foreign_key "cat_rental_requests", "users", column: "requester_id"
+  add_foreign_key "cats", "users", column: "owner_id"
+end
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/db/seeds.rb b/rails/projects/helpers_layouts_mailers/db/seeds.rb
new file mode 100644
index 0000000..555c37c
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/db/seeds.rb
@@ -0,0 +1,7 @@
+# This file should contain all the record creation needed to seed the database with its default values.
+# The data can then be loaded with the bin/rails db:seed command (or created alongside the database with db:setup).
+#
+# Examples:
+#
+#   movies = Movie.create([{ name: "Star Wars" }, { name: "Lord of the Rings" }])
+#   Character.create(name: "Luke", movie: movies.first)
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/lib/assets/.keep b/rails/projects/helpers_layouts_mailers/lib/assets/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/lib/tasks/.keep b/rails/projects/helpers_layouts_mailers/lib/tasks/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/log/.keep b/rails/projects/helpers_layouts_mailers/log/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/public/404.html b/rails/projects/helpers_layouts_mailers/public/404.html
new file mode 100644
index 0000000..cb93ac7
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/public/404.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The page you were looking for doesn't exist (404)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/404.html -->
+  <div class="dialog">
+    <div>
+      <h1>The page you were looking for doesn't exist.</h1>
+      <p>You may have mistyped the address or the page may have moved.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/public/422.html b/rails/projects/helpers_layouts_mailers/public/422.html
new file mode 100644
index 0000000..aa1a374
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/public/422.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The change you wanted was rejected (422)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/422.html -->
+  <div class="dialog">
+    <div>
+      <h1>The change you wanted was rejected.</h1>
+      <p>Maybe you tried to change something you didn't have access to.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/public/500.html b/rails/projects/helpers_layouts_mailers/public/500.html
new file mode 100644
index 0000000..0fd6fca
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/public/500.html
@@ -0,0 +1,66 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>We're sorry, but something went wrong (500)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/500.html -->
+  <div class="dialog">
+    <div>
+      <h1>We're sorry, but something went wrong.</h1>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/public/apple-touch-icon-precomposed.png b/rails/projects/helpers_layouts_mailers/public/apple-touch-icon-precomposed.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/public/apple-touch-icon.png b/rails/projects/helpers_layouts_mailers/public/apple-touch-icon.png
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/public/favicon.ico b/rails/projects/helpers_layouts_mailers/public/favicon.ico
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/public/robots.txt b/rails/projects/helpers_layouts_mailers/public/robots.txt
new file mode 100644
index 0000000..0285b2d
--- /dev/null
+++ b/rails/projects/helpers_layouts_mailers/public/robots.txt
@@ -0,0 +1 @@
+# See https://www.robotstxt.org/robotstxt.html for documentation on how to use the robots.txt file
\ No newline at end of file
diff --git a/rails/projects/helpers_layouts_mailers/tmp/.keep b/rails/projects/helpers_layouts_mailers/tmp/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/tmp/pids/.keep b/rails/projects/helpers_layouts_mailers/tmp/pids/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/helpers_layouts_mailers/vendor/.keep b/rails/projects/helpers_layouts_mailers/vendor/.keep
new file mode 100644
index 0000000..e69de29
diff --git a/rails/projects/music_app/.gitattributes b/rails/projects/music_app/.gitattributes
new file mode 100644
index 0000000..34fb547
--- /dev/null
+++ b/rails/projects/music_app/.gitattributes
@@ -0,0 +1,7 @@
+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
\ No newline at end of file
diff --git a/rails/projects/music_app/.gitignore b/rails/projects/music_app/.gitignore
new file mode 100644
index 0000000..4f0da6f
--- /dev/null
+++ b/rails/projects/music_app/.gitignore
@@ -0,0 +1,26 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
\ No newline at end of file
diff --git a/rails/projects/music_app/README-bonus.md b/rails/projects/music_app/README-bonus.md
new file mode 100644
index 0000000..92b0b44
--- /dev/null
+++ b/rails/projects/music_app/README-bonus.md
@@ -0,0 +1,173 @@
+# Music App (Bonus)
+
+**[Live Demo!][live-demo]**
+
+[live-demo]: https://aa-music-app.herokuapp.com
+
+## Bonus time!
+
+Great work! Here are some bonus features to add to your music inventory
+application.
+
+### Bonus I: Additional authentication features
+
+Spam-bots keep signing up for your inventory management application. Defeat them
+by sending out an activation email. You'll ask users to click a link to activate
+their account when they sign up.
+
+#### Adding activation columns
+
+To enable account activation, you need to add two columns to your `users` table:
+an `activated` boolean field to track the status of user accounts and an
+`activation_token` column that you will use to activate accounts. Accounts
+should start out deactivated. You should also add a check to see if a user is
+active before logging them in.
+
+#### Setting up Action Mailer
+
+Whenever a user signs up on your site, use [Action Mailer] to send them an
+email. If you used the `--minimal` flag when creating your app, then Action
+Mailer is not installed. To enable its features, open __config/application.rb__
+and uncomment the `require "action_mailer/railtie"` line. That's it! Now Action
+Mailer is ready to go.
+
+Run `rails g mailer User`. This will create the following files:
+
+- __app/mailers/user_mailer.rb__
+- __app/mailers/application_mailer.rb__
+- __app/views/user_mailer__
+- __app/views/layouts/mailer.text.erb__
+- __app/views/layouts/mailer.html.erb__
+
+(If you included tests in your app, it will also produce
+__test/mailers/user_mailer_test.rb__ and
+__test/mailers/previews/user_mailer_preview.rb__.)
+
+__application_mailer.rb__ and the two layouts would already have been among your
+app's files if Action Mailbox had been included when generating your app. The
+generator only creates these three files if they do not already exist.
+
+Like controllers, mailers have actions that correspond to views. In
+__user_mailer.rb__, define an `activation_email` action that takes in a user.
+Save the user as an instance variable, then call `mail` with an options hash
+containing values for `to` and `subject`. It should look something like this:
+
+```ruby
+class UserMailer < ApplicationMailer
+  def activation_email(user)
+    @user = user
+    mail(to: user.email, subject: "Welcome to Music App! Please activate your account.")
+  end
+end
+```
+
+Next, set up your emails/views. Inside the __app/views/user_mailer/__ folder,
+create a corresponding __activation_email.html.erb__ file. This file contains
+the HTML that will be sent in your email. As with normal views and controllers,
+you can access any instance variables that were set in the mailer:
+
+```html
+<!-- app/views/user_mailer/activation_email.html.erb -->
+
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta content='text/html; charset=UTF-8' http-equiv='Content-Type' />
+  </head>
+  <body>
+    <h1>Welcome <%= @user.email %>, </h1>
+    <!-- ... -->
+  </body>
+</html>
+```
+
+The email should contain a link to activate the new account. Add a custom route
+for a new action such as `UsersController#activate`. (You can use the
+[`collection`] method to add additional routes to the `users` resources.) Then
+in the email, add a URL to `/users/activate?activation_token=...`.
+
+When you have finished your HTML template, repeat the process in
+__app/views/user_mailer/activation_email.text.erb__ using only text. Since not
+all email readers support HTML, it is best practice always to send both HTML and
+plain-text versions of your email.
+
+> Note: When generating a new mailer, you can specify actions to create like
+> this:
+
+  ```sh
+  rails g mailer User activation_email
+  ```
+
+> This will include a basic skeleton for `activation_email` in
+> __app/mailers/user_mailer.rb__ and generate the
+> __app/views/user_mailer/activation_email.text.erb__ and
+> __app/views/user_mailer/activation_email.html.erb__ files.
+
+The custom `activate` controller action should verify that the user clicked the
+link in their email. If the token in the query string matches with the token in
+the database, it should activate the account and flip the boolean. **Hint:** You
+can use [Active Record's toggle method][ar-toggle] to flip the value of a
+boolean attribute.
+
+Finally, change what happens on a successful `save` in your `UsersController`
+`create` action. You no longer want to activate the user instantly and log them
+in. Now you want to send them an email, which you do like this:
+
+```rb
+UserMailer.activation_email(@user).deliver_now
+```
+
+Add a `flash` notice announcing the account's successful creation and
+instructing the user to check their email. Redirect back to the new session
+page.
+
+[Action Mailer]: https://guides.rubyonrails.org/action_mailer_basics.html
+[`collection`]: https://guides.rubyonrails.org/routing.html#adding-collection-routes
+[ar-toggle]: http://api.rubyonrails.org/classes/ActiveRecord/Persistence.html#method-i-toggle
+
+#### Testing your Action Mailer
+
+To test your mailer setup, do the following:
+
+- Run `brew install mailhog`.
+- Run `mailhog`.
+- Open `localhost:8025` in your browser; this will be your inbox.
+- Put the following code in your __config/application.rb__:
+
+```ruby
+config.action_mailer.default_url_options = { host: 'localhost:3000' }
+config.action_mailer.delivery_method = :smtp
+config.action_mailer.smtp_settings = { address: '0.0.0.0', port: 1025 }
+config.action_mailer.raise_delivery_errors = false
+```
+
+> Note: Putting these lines in __application.rb__ will apply them in all three
+> environments (`test`, `development`, and `production`). If you need to
+> differentiate the configuration for the different environments--e.g., the
+> `host` will not be `localhost:3000` in `production`--move the lines to the
+> appropriate file(s) in __config/environments/__.
+
+Restart your rails server, sign up for your site, and check your MailHog inbox!
+
+### Bonus II: Admin Accounts
+
+Let's add admin accounts for people from your record label. This way your PR
+department can remove notes that don't reflect well on your properties.
+
+- Add an `admin` boolean to the `users` table.
+  - Only admin users should be allowed to create/update/destroy inventory
+    objects.
+    - Hide the links from regular users, and make sure to check if someone is an
+      admin using a before filter on admin-only controller actions.
+- Add a `users` index visible only to admin users.
+  - Put a button next to each user which, when clicked, makes that user an
+    admin.
+
+### Bonus III: Styling
+
+Style your app!
+
+- Change the colors and font sizes for different elements.
+- Put your content in tables and play around with the positioning.
+- See if you can make your sign-up and log-in forms look nicer. Try centering
+  them or adding a border.
\ No newline at end of file
diff --git a/rails/projects/music_app/README-ph1.md b/rails/projects/music_app/README-ph1.md
new file mode 100644
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--- /dev/null
+++ b/rails/projects/music_app/README-ph1.md
@@ -0,0 +1,191 @@
+# Music App (Phase I)
+
+**[Live Demo!][live-demo]**
+
+[live-demo]: https://aa-music-app.herokuapp.com
+
+## Phase I: Band/Album/Track
+
+Put aside the `user` features for a moment; you're going to build out your
+inventory system.
+
+You want to build out a feature/resource at a time. Follow this order per
+resource:
+
+- Migrations
+- Model definition (validations, associations, helper methods)
+- Routes
+- Controller + controller actions
+- Views (should coincide with the actions that render them)
+
+Here's what you need for each resource:
+
+### Bands
+
+- Create a `bands` table with a unique `name` column (required).
+- Create a `Band` model with a validation to ensure that `name` is unique and
+  not null.
+- Create the following RESTful routes:
+
+```sh
+bands     GET    /bands(.:format)                       bands#index
+          POST   /bands(.:format)                       bands#create
+new_band  GET    /bands/new(.:format)                   bands#new
+edit_band GET    /bands/:id/edit(.:format)              bands#edit
+band      GET    /bands/:id(.:format)                   bands#show
+          PATCH  /bands/:id(.:format)                   bands#update
+          PUT    /bands/:id(.:format)                   bands#update
+          DELETE /bands/:id(.:format)                   bands#destroy
+```
+
+- Create `BandsController` and actions/views to handle each of the routes.
+  - You may have noticed that your four member actions--`show`, `edit`,
+    `update`, and `destroy`--always begin by finding the specified member.
+    Create a `before_action` filter, `set_band`, that finds the specified band
+    and assigns it to `@band` before those four actions. (Make sure it only runs
+    before those 4 actions!) This is a common Rails pattern.
+  - Create each view after finishing the controller action that would render it
+  - Test as you go! Remember, you can use Postman to test `POST`, `PATCH`, and
+    `DELETE` actions prior to building your form views.
+  - To test with Postman, you will need to disable CSRF protection. Add the line
+    `config.action_controller.default_protect_from_forgery = false` right
+    underneath the line `config.load_defaults X.X` in __config/application.rb__.
+    Remember, this should only be done while you are working in development.
+
+### CSRF time!
+
+- Re-enable CSRF protection. Remove the line
+  `config.action_controller.default_protect_from_forgery = false` from
+  __config/application.rb__. The default value of
+  `config.action_controller.default_protect_from_forgery` is `true`.
+- Any form that does not upload the `form_authenticity_token` will cause Rails
+  to throw an error because it won't know whether ot not the `POST` request is
+  coming "cross-site".
+- Fix your forms, friend!
+
+### Albums
+
+Follow the same pattern for a new resource, `Albums`.
+
+An `Album` should:
+
+- Not be called `Record`, as Active Record uses `record_id` internally
+- Belong to a `band` (don't forget to add the association to `Band` as well)
+- Have a `title` and `year`
+- Make sure the `title` is unique among the band's albums
+- Designate whether it is a `live` or `studio` album
+  - HINT: use a boolean paired with a reasonable default value
+- Have the following routes:
+  
+  ```sh
+  new_band_album GET    /bands/:band_id/albums/new(.:format)   albums#new
+          albums POST   /albums(.:format)                      albums#create
+      edit_album GET    /albums/:id/edit(.:format)             albums#edit
+           album GET    /albums/:id(.:format)                  albums#show
+                 PATCH  /albums/:id(.:format)                  albums#update
+                 PUT    /albums/:id(.:format)                  albums#update
+                 DELETE /albums/:id(.:format)                  albums#destroy
+  ```
+
+  > **Note:** This is the first time that you'll be using nested routes in a
+  > project. **Please make sure your routes for albums exactly match the ones
+  > above.** Check out the nested routes reading that you may have missed if the
+  > motivation and syntax for creating nested routes is still unclear. Don't
+  > hesitate to ask a TA for assistance!
+
+- Once you have implemented band creation using the route configuration laid out
+  above, think for a while about what code in your app (specifically, in your
+  controllers and views) would need to change to accommodate a `create` route
+  that was also nested.
+
+- For the views:
+  - Have a drop-down to select which `Band` recorded the `Album`. Use `selected`
+    to default-select the appropriate `Band` in the drop-down.
+  - Use radio buttons to select whether the album is a live or studio album.
+    Don't use a column named `type`, since Rails uses this for a special purpose
+    and everything will break. Use `checked` to default select the appropriate
+    value.
+  - Make sure to provide links back to the album's band and make edit/delete
+    buttons visible from the album's `show` page.
+  - Update the `Band` `show` page to list/link to all of the band's albums and
+    create a new one.
+
+**When you reach this point, request a code review from an instructor.**
+
+### Tracks
+
+Yet again, follow the same pattern for a new resource, `Tracks`.
+
+A `Track` should:
+
+- Belong to an `album` (make sure to also add associations to `Band` and
+  `Album`)
+- Have a `title`, `ord` (track number), and optional `lyrics`
+- Ensure that track numbers are unique within an album
+- Designate whether it is a `regular` or `bonus` track
+- Have the following routes:
+
+  ```sh
+  new_album_track GET    /albums/:album_id/tracks/new(.:format) tracks#new
+           tracks POST   /tracks(.:format)                      tracks#create
+       edit_track GET    /tracks/:id/edit(.:format)             tracks#edit
+            track GET    /tracks/:id(.:format)                  tracks#show
+                  PATCH  /tracks/:id(.:format)                  tracks#update
+                  PUT    /tracks/:id(.:format)                  tracks#update
+                  DELETE /tracks/:id(.:format)                  tracks#destroy
+  ```
+
+  **Once again, please make sure the routes you make look exactly like the ones
+  above.**
+
+- For the views:
+  - You need a drop down to select the `Album`. Again, default select the
+    appropriate `Album` in the drop down.
+  - Use radio buttons to mark a track as a "bonus" or "regular" track. Again,
+    default select the appropriate value.
+  - Use a `textarea` to allow the user to enter lyrics.
+  - Again, provide links to the track's album and make edit/delete buttons
+    visible from the track's `show` page.
+  - Update the `Album` `show` page to list/link to all of the album's tracks and
+    create a new one.
+
+Add `dependent: :destroy` to applicable associations. Remember that this option
+causes associated objects to be destroyed on `destroy`.
+
+### Requiring login
+
+Make sure a user cannot view any of the `Band`, `Album`, or `Track` data without
+first logging in. If they are not logged in, bounce them to the sign-in url with
+a `before_action`. Since you want to cover almost every action, put the
+`before_action` in your `ApplicationController`. It will then be inherited by
+all of your other controllers.
+
+There are a couple of actions, however, where you **don't** want the user to be
+logged in. More specifically, you don't want to require that someone is logged
+in when they are trying to sign up or log in. To except certain actions from an
+inherited `before_action`, use `skip_before_action` in the appropriate
+controller. For example, in this case you should add the following to your
+`SessionsController`:
+
+```rb
+class SessionsController < ApplicationController
+  skip_before_action :require_logged_in, only: %i(new create)
+  # ...
+end
+```
+
+This will skip the `require_logged_in` filter before running your
+`SessionsController`'s`new` and `create` actions.
+
+Similarly, in your `UsersController`, skip the login requirement for every
+action `except` `show`.
+
+### Style it
+
+Spend no more than 20 minutes adding some CSS to your views. Some ideas:
+
+- Improve spacing/alignment of form elements
+- Improve upon default list styling with a fancy flexbox grid
+- Add page headers
+
+Once you finish styling, head on to [Phase II.](README-ph2-4.md)
\ No newline at end of file
diff --git a/rails/projects/music_app/README-ph2-4.md b/rails/projects/music_app/README-ph2-4.md
new file mode 100644
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--- /dev/null
+++ b/rails/projects/music_app/README-ph2-4.md
@@ -0,0 +1,74 @@
+# Music App (Phases II-IV)
+
+**[Live Demo!][live-demo]**
+
+[live-demo]: https://aa-music-app.herokuapp.com
+
+## Phase II: Notes
+
+In this phase you will allow users to write notes about tracks. You can "embed"
+the note form on the track show page.
+
+- Add a `Note` model. Users can make a `Note` on any `Track`.
+  - `Note`s will belong to an author and a track.
+  - Use the column type `text` to store arbitrarily long notes.
+  - Add appropriate indexes, constraints, and validations.
+- On the `Track` `show` page, display the track's `Note`s.
+  - Write a __notes/_note.html.erb__ partial.
+  - Render the content, plus the author's email.
+- Put a `Note` form on the `Track` `show` page.
+  - Use a __notes/_form.html.erb__ partial.
+  - Use a `textarea` in the form. Do not store the `user_id` in a hidden field.
+    **Why?**
+  - On submit of a new `Note`, redirect back to the track.
+  - For this form, you can `redirect_to` the track even on validation failure.
+    This "blanks out" the note content in the form. That would be bad, but the
+    only real validation is that the content is not blank...
+- Add destroy buttons for notes to the `notes/_note` partial.
+  - Only show the button if the `current_user` authored the note.
+  - In the controller, ensure that a user is not allowed to destroy a note
+    unless they authored it.
+    - **Hint:** You don't need a `before_action` for this; you can accomplish it
+      by cleverly constructing your note search.
+
+## Phase III: Helpers
+
+In a fit of poor judgment, you have decided to display your lyrics like this,
+with a music note before every line:
+
+```sh
+♫ And I was like baby, baby, baby, oooh
+♫ Like baby, baby, baby, nooo
+♫ Like baby, baby, baby, oooh
+♫ I thought you'd always be mine (mine)
+```
+
+Write an `ugly_lyrics(lyrics)` method inside the `ApplicationHelper` module in
+__app/helpers/application_helper.rb__. The method should:
+
+- Break up the lyrics on newlines.
+- Insert a ♫ at the start of each line (the HTML entity that will render as a
+  music note is `&#9835;`).
+- Properly escape the user input (avoid HTML injection attacks).
+- Wrap the lyrics in a [`pre` tag][pre-tag] so that the newlines are respected
+  (in a`<pre>` or _preformatted text tag_, whitespace is preserved).
+- Mark the produced HTML as safe for insertion (otherwise your `<pre>` tag will
+  get escaped when you insert it into the template).
+
+## Phase IV: Validating form input
+
+Now that you've got a site and users, they are bound to start making mistakes!
+
+On each form view, include the logic to display any errors that your validations
+return.
+
+- In your view, check if `@___.errors.full_messages` exists.
+- If so, display each of them in its own stylish div!
+
+## Next steps
+
+Congratulations, you've finished the basic project! If you still have time, head
+over to the [bonus phases](README-bonus.md) to learn--among other things--how to send out an
+account activation email using Action Mailer.
+
+[pre-tag]: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/pre
\ No newline at end of file
diff --git a/rails/projects/music_app/README.md b/rails/projects/music_app/README.md
new file mode 100644
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--- /dev/null
+++ b/rails/projects/music_app/README.md
@@ -0,0 +1,115 @@
+# Music App
+
+**[Live Demo!][live-demo]**
+
+Today you're going to build an inventory system for record labels. This app will
+let the labels track their `Band`s, `Album`s, and `Track`s. Additionally, you'll
+offer user accounts so users can comment on the inventory.
+
+[live-demo]: https://aa-music-app.herokuapp.com
+
+## Learning goals
+
+By the end of this project, you should be able to
+
+- Build User Auth without looking at old code or demos
+- Nest routes
+- Link between different views using `a` tags and Rails URL helpers
+- Trigger controller actions from views using forms and links
+- Check that a current user exists before displaying content
+
+**Throughout this project, do not use `form_with`.**
+
+## Warm up: Authentication
+
+Create a new Rails application and do any initial setup needed to get it ready
+to go. (If you have forgotten the basic steps for setting up a Rails app, look
+at the instructions for one of your past projects.) Use `postgresql` for your
+database. You can grab __.gitattributes__ and __.gitignore__ files from one of
+your past projects or the repo at the `Download Project` button below.
+
+Create a `User` model and bake in the prerequisites of authentication. Use email
+addresses in lieu of usernames; in a bonus phase, you'll use the email addresses
+to send confirmation emails and other spam.
+
+See if you can build auth without looking back at any old code or demos. Here's
+a rough guide if you get stuck:
+
+In the `users` table, you'll want to store an `email`, `password_digest`, and
+`session_token`. Make sure to add database constraints (require all fields) and
+indexes to ensure uniqueness of `email`s and speed up the lookup by
+`session_token`.
+
+- Write methods to deal with the session token:
+  `User#generate_unique_session_token`, `User#reset_session_token!` and
+  `User#ensure_session_token`.
+- Write a `User#password=(password)` method which actually sets the
+  `password_digest` attribute using [BCrypt][bcrypt-documentation], and a
+  `User#is_password?(password)` method to check the users' password when they
+  log in.
+
+  > **N.B.**: Be careful setting instance variables in Active Record. You can't
+  > just set `@password_digest`. Instead, use `self.password_digest =` in
+  > `#password=`. (`self.___ =` calls an Active Record setter method that
+  > updates the state saved by `self.save`; `@___ =` makes a new instance
+  > variable unrelated to `self.save`.)
+
+- Remember that in the `User` model, you'll want to use a `before_validation`
+  [callback] to set the `session_token` before validation if it's not present.
+- Write a `User::find_by_credentials(email, password)` method.
+
+Next write a `UsersController` and `SessionsController`.
+
+- Write methods on the `UsersController` to allow new users to sign up.
+  - Users should be logged in immediately after they sign up.
+- Create a `SessionsController` but no `Session` model.
+  - Write controller methods and the accompanying routes so that users can log
+    in and log out. Should session be a singular resource?
+  - `SessionsController#create` should reset the appropriate user's
+    `session_token` and `session[:session_token]`.
+  - For now just redirect them to a `UsersController#show` page which simply
+    displays that user's email.
+
+Finally, take some time to refactor out shared code and add some convenience
+methods to `ApplicationController`. Make sure to include the appropriate methods
+in your views as helper methods (e.g., `helper_method :current_user`). At a
+minimum, you'll probably want to define the following methods:
+
+- `#current_user` to return the current user.
+- `#logged_in?` to return a boolean indicating whether anyone is signed in.
+- `#login!(user)` reset the `user`s session token and cookie
+
+### Routes summary
+
+Your app should have routes for:
+
+```sh
+    session POST   /session(.:format)                     sessions#create
+            DELETE /session(.:format)                     sessions#destroy
+new_session GET    /session/new(.:format)                 sessions#new
+      users POST   /users(.:format)                       users#create
+   new_user GET    /users/new(.:format)                   users#new
+       user GET    /users/:id(.:format)                   users#show
+```
+
+Create log-in/sign-up views and edit the __application.html.erb__ layout so that
+a logged-in user is shown a "sign-out" button and a logged-out user is shown
+links to sign-up or sign-in pages.
+
+### Styling
+
+Spend a few minutes adding some styling to your session forms.
+
+- Add a `Music App` header with a snazzy font to `application.html.erb`.
+- Use `flex` to display your logged-in or logged-out info on the right-hand side
+  of your `Music App` header.
+- Default link styling is pretty ugly. While keeping your `<a>` tags, make your
+  links look more like buttons by using `background-color` and `border-radius`.
+- Improve your session forms by changing the spacing and alignment of their
+  elements.
+
+Great job setting up authentication! Now on to [Phase I](README-ph1.md), where you will start
+implementing elements specific to your music inventory app.
+
+[bcrypt-documentation]: https://github.com/codahale/bcrypt-ruby
+[callback]: https://guides.rubyonrails.org/active_record_callbacks.html#available-callbacks
\ No newline at end of file
diff --git a/rails/projects/ninety_nine_cats_i/README-ph2.md b/rails/projects/ninety_nine_cats_i/README-ph2.md
new file mode 100644
index 0000000..4a3c659
--- /dev/null
+++ b/rails/projects/ninety_nine_cats_i/README-ph2.md
@@ -0,0 +1,111 @@
+# 99cats (Phase II)
+
+**[Live Demo!][live-demo]**
+
+[live-demo]: https://aa-99-cats.herokuapp.com/
+
+## Phase II: `CatRentalRequest`
+
+In this phase, you will create a `CatRentalRequest` model with appropriate
+validations, build a form to create such a request, and integrate that form into
+the rest of your site.
+
+### `CatRentalRequest` model
+
+Make a `CatRentalRequest` migration and model. Attributes should include:
+
+* `cat_id` (bigint)
+  * Use the `references` type in your migration to set this up.
+* `start_date` (date)
+* `end_date` (date)
+* `status` (string)
+  * Should start out as `'PENDING'` but can be switched to `'APPROVED'` or
+    `'DENIED'`.
+
+In the migration,
+
+* Add NOT NULL constraints to everything except `timestamps`.
+* Make `'PENDING'` the default value for `status`.
+* Make sure that your migration adds an index and `foreign_key` constraint on
+  `cat_id`.
+
+In the model,
+
+* Add an inclusion validation on `status`.
+* Add presence validations where appropriate.
+* Add associations between `CatRentalRequest` and `Cat`.
+* Make sure that when a `Cat` is deleted, all of its rental requests are also
+  deleted. (The foreign key constraint you set above requires this.) Use
+  `dependent: :destroy`.
+
+### Custom validations
+
+`CatRentalRequest`s should not be valid if they overlap with an approved
+`CatRentalRequest` for the same cat. A single cat can't be rented out to two
+people at once! You will write a custom validation for this.
+
+First, write a method `#overlapping_requests` to get all the `CatRentalRequest`s
+that overlap with the one you are trying to validate:
+
+* Be sure to use Active Record to do this. It may be tempting just to get
+  `CatRentalRequests.all` and then do all the filtering in Ruby, but this
+  would be wasteful. You don't want to create objects you don't need. Your
+  database is really good at solving this kind of problem, so use it!
+* The method should return an `ActiveRecord::Relation` so you can chain more
+  methods onto it later.
+* The `CatRentalRequest` you are trying to validate should not appear in the
+  list of `#overlapping_requests`.
+* The method should return the requests for the current cat.
+* The method should work for both saved and unsaved `CatRentalRequests`.
+* Consider the following cases:
+  * A cat rental request starting on 02/25/22 and ending on 02/27/22.
+  * There is a overlap if another cat rental also starts on the same day
+    (02/25/22).
+  * There is a overlap if another cat rental request starts on the return day
+    (02/27/22).
+  * There is a overlap if another cat rental request starts between the start
+    and end dates (02/26/22).
+* Hint: Consider the case(s) where requests would **NOT** overlap and then code
+  the negation.
+* Beware of SQL ternary logic (values: true, false, unknown).
+
+Next, write a method `#overlapping_approved_requests` that returns all the
+overlapping requests with `'APPROVED'` status. You should be able to use your
+`#overlapping_requests` method.
+
+Now you can write your [custom validation],
+`#does_not_overlap_approved_request`. All you need to do is call
+`#overlapping_approved_requests` and check whether any [`#exists?`][exists].
+
+[custom validation]: https://guides.rubyonrails.org/active_record_validations.html#custom-methods
+[exists]: https://api.rubyonrails.org/v7.0.2/classes/ActiveRecord/FinderMethods.html#method-i-exists-3F
+
+### Routes, controller, & `new` view
+
+* Create `new` and `create` routes for your rental requests in your routes file.
+  Nest an additional `new` route under `cats` to create a
+  `/cats/:cat_id/cat_rental_requests/new` route. You will use this route to
+  initiate rental requests for a specific cat (i.e., from a cat's `show` page).
+* Create a controller and build out those two actions. (Remember to use strong
+  params for mass assignment!)
+* Add a `new` request form to submit rental requests.
+  * Use a dropdown to select the `Cat` desired. Your rental request form should
+    upload a `Cat` `id`.
+  * Use the `date` input type for selecting the request's start and end dates.
+  * Use the [`required`] attribute to ensure that all three fields are filled in
+    before submitting.
+* Edit the `Cat` `show` page to show existing requests
+  * If there are no rental requests, just report that the cat--personalize this
+    by using the cat's `name`--has no requests.
+  * Otherwise, create a table to show the `start_date`, `end_date`, and `status`
+    of each request.
+  * Use `order` to sort them by `start_date`.
+* Add a link to the `Cat` `show` page to initiate a rental request for that cat.
+  (Use your nested route!)
+* Add a link to the `Cat` `index` page to initiate a generic rental request.
+
+Test your work in the browser as you go.
+
+[`required`]: https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/required
+
+When you finish, head on to [Phase III](README-ph3.md) (approving/denying requests)!
\ No newline at end of file
diff --git a/rails/projects/ninety_nine_cats_i/README-ph3.md b/rails/projects/ninety_nine_cats_i/README-ph3.md
new file mode 100644
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--- /dev/null
+++ b/rails/projects/ninety_nine_cats_i/README-ph3.md
@@ -0,0 +1,82 @@
+# 99cats (Phases III, Bonus)
+
+**[Live Demo!][live-demo]**
+
+[live-demo]: https://aa-99-cats.herokuapp.com/
+
+## Phase III: Approving/Denying requests
+
+In today's final phase, you will enable users to approve or deny any `Cat`'s
+`CatRentalRequest`.
+
+### Write `approve!` and `deny!` methods
+
+Currently, all `CatRentalRequest` statuses are set to `'PENDING'`. When
+approving a `CatRentalRequest` (changing the cat rental request's status to
+`'APPROVED'`), all other conflicting `CatRentalRequest` statuses will be denied
+(changing the cat rental request's status to `'DENIED'`).
+
+* Add a helper method `#overlapping_pending_requests` that returns all the
+  overlapping requests with status `'PENDING'`. You should be able to use your
+  `#overlapping_requests` method.
+* Add a method `#approve!` to the rental request model. When calling the
+  `#approve!` on an instance of `CatRentalRequest`:
+  * Change the current instance's status from `'PENDING'` to `'APPROVED'`.
+  * Save the instance into the database.
+  * Deny all conflicting rental requests by calling
+    `'overlapping_pending_requests'` and changing the statuses of the returned
+    requests to `'DENIED'`.
+* All the work of `#approve!` should occur in a single
+  **[transaction][transaction-api]**.
+  * Usually when you want to make several related updates to the DB, you will
+    want to group them in a transaction.
+* Write a `#deny!` method; this one is easier!
+
+[transaction-api]:
+  https://api.rubyonrails.org/v7.0.2/classes/ActiveRecord/Transactions/ClassMethods.html
+
+### Add Buttons
+
+* On the `Cat` show page, make a button to approve or deny a cat request.
+* You may add two member routes to `cat_rental_requests`: `approve` and `deny`.
+* Only show these buttons if a request is pending.
+* You may want to add a convenient `CatRentalRequest#pending?` method.
+
+## Bonus
+
+Style your website to look similar to the live demo. You can add your CSS to the
+__app/stylesheets/application.css__ file. A few hints to get you started:
+
+* The cat images are all sourced from [https://placekitten.com/]. The `index`
+  page uses number [231], the `show` page, number [300]. Feel free to use
+  these particular images or pick others that you prefer!
+* The `+`s next to `Add Cat` and `Request a Rental` on the `index` page are
+  [Font Awesome] icons. If you don't want to explore Font Awesome at the moment,
+  you can just style a typed `+`.
+* The live demo uses the Google Font [`Amatic SC`]. You can include this font
+  in your project by adding the following line inside the `<head>` of your
+  document in __app/views/layouts/application.html.erb__:
+
+  ```html
+  <link href="https://fonts.googleapis.com/css?family=Amatic+SC:400,700" rel="stylesheet">
+  ```
+
+* Don't forget to add a `description` field to the `Cat` `show` page table if
+  you haven't already.
+
+Have fun styling!
+
+[https://placekitten.com/]: https://placekitten.com/
+[231]: https://placekitten.com/g/231/231
+[300]: https://placekitten.com/g/300/300
+[Font Awesome]: https://fontawesome.com/
+[`Amatic SC`]: https://fonts.google.com/specimen/Amatic+SC
+
+## What you've learned
+
+Congratulations! In this project, you learned how to build a model with
+validations and default values, and how to add methods and custom validations to
+it. You also practiced building `new` and `edit` forms using different types of
+HTML input elements, partials to keep your code DRY, and hidden fields to set a
+form's method. Finally, if you made it through the bonus, then you also
+exercised your CSS styling skills. Well done!
\ No newline at end of file
diff --git a/rails/projects/ninety_nine_cats_i/README.md b/rails/projects/ninety_nine_cats_i/README.md
new file mode 100644
index 0000000..b618cb0
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+++ b/rails/projects/ninety_nine_cats_i/README.md
@@ -0,0 +1,250 @@
+# 99cats
+
+This project asks you to clone the (now defunct) dress rental website 99dresses.
+Instead of a site for dresses, however, you will make a rental site for cats.
+
+**[Live Demo!][live-demo]**
+
+## Learning goals
+
+By the end of this project, you should be able to
+
+* Build a model with validations and default values
+* Add methods and custom validations to a Rails model
+* Build Rails views for `new` and `edit` forms
+  * Use a hidden field to set the form's method
+  * Separate common form elements into a partial that both forms use
+  * Show data and perform actions based on the form's type
+  * Use `select` and `input` HTML elements
+
+## Phase 0: Setup
+
+Create a new Rails app called `ninety-nine-cats`. Remember to include the flags
+to set the database, to skip setting up a Git repo, to skip tests, and to use a
+minimal build. (Refer to the Rails Setup reading in the sidebar if you've
+forgotten how to do this.)
+
+Grab the __.gitignore__ and __.gitattributes__ files from the starter repo at
+the `Download Project` button below and copy them into the root directory of
+your project.
+
+If you prefer to use `byebug` instead of `debug` as your debugger, then replace
+`debug` with `byebug` in your Gemfile and make sure your __.gitignore__ includes
+__.byebug_history__. Add any other gems you want to install (e.g., `annotate`,
+`better_errors`, `binding_of_caller`, `pry-rails`). If you make any changes to
+your Gemfile, run `bundle install` to incorporate them into your project.
+
+Next, set up your Postgres database by running `rails db:create`.
+
+Finally, you don't need to worry about CSRF attacks today. (And no, you're not
+supposed to know what that is yet!) Take a walk on the wild side by adding the
+line
+
+```rb
+config.action_controller.default_protect_from_forgery = false
+```
+
+right underneath the `config.load_defaults X.X` line in
+__config/application.rb__.
+
+[live-demo]: https://aa-99-cats.herokuapp.com/
+
+## Phase I: `Cat`
+
+In this first phase, you will set up your `cats` table in the database. You will
+then build a basic web interface for creating, accessing, and manipulating the
+data stored in the table. You will also practice using partials to keep the code
+in your `views` DRY.
+
+### `Cat` model
+
+Build a `Cat` migration and model. Attributes should include:
+
+* `birth_date`
+  * Use the `date` column type.
+* `color`
+* `name`
+* `sex`
+  * Represent as a one-character string. Use the [`:limit`][limit-docs] option
+    in your migration to make a `string` column of length 1.
+* `description`
+  * Use a `text` column to store arbitrarily long text describing fond memories
+    the user has of the `Cat`.
+* `timestamps`
+
+Add database-level NOT NULL constraints to all of the columns except
+`description` and `timestamps`, then migrate.
+
+Once you've migrated, add the following validations in the model:
+
+* `presence` where appropriate
+* `inclusion` ensuring that `color` comes from a preset list of possible
+  `CAT_COLORS` that you define. (You'll need to access the colors again in the
+  views, so store them in a constant inside your `Cat` class.)
+* `inclusion` ensuring that `sex` is `"M"` or `"F"`
+
+Then add a [custom validation][custom validations]
+`:birth_date_cannot_be_future` to ensure that the cat's `birth_date` is not in
+the future. Here you can see the benefit of having declared `birth_date` to be
+of type `date`: Active Record magically deserializes the string input into a
+Ruby `Date` object. So, e.g., you can do this:
+
+```ruby
+kitty = Cat.new(birth_date: '2015/01/20')
+kitty.birth_date #=> #<Date: 2015-01-20>
+```
+
+> Note: Naming a `Cat` instance `cat`--e.g., `cat = Cat.new(birth_date:
+> '2022/01/20')`--will cause an error in pry because `cat` is a reserved word.
+
+Because Active Record stores `birth_date` as a `Date`, you have access to all
+the methods listed in the [Ruby `Date` docs][date-docs]. At least one of those
+methods should prove helpful in writing this validation.
+
+Note, too, that the `valid?` method bases its result on whether or not the
+validations put anything into the `errors` collection. You will accordingly want
+to `add` an error to `errors` if the validation fails. **Hint**: if you are
+stuck on how to write this validation, the example in the Rails Guide to [custom
+validations] should provide a helpful model.
+
+Finally, once you have finished adding all the validations, write an `#age`
+method that uses `birth_date` to calculate age. Remember that you have access to
+all the methods listed in the [Ruby `Date` docs][date-docs]. You also might want
+to check out the `time_ago_in_words` method in the [Rails docs][time-ago].
+
+> Note: `DateHelper`--see the lefthand sidebar in the Rails docs--is a module
+> that needs to be added to the `Cat` model if you want access to the methods
+> mentioned at the Rails link. To do this, require `action_view` at the top of
+> your `cat.rb` file, then `include ActionView::Helpers::DateHelper` inside your
+> `Cat` class.
+
+When you have finished building out your model, test it in the Rails console
+(`rails c`). First, test your validations: create a blank `Cat` (`c = Cat.new`)
+and try to `save!` it. This should trigger all of your standard validations.
+
+Next, set the `birth_date` field for your cat for some time in the future--use a
+string with a four-digit year, e.g., '1/1/2030'--and try to `save!` it. That
+should fail your custom validation. Then change the `birth_date` to a valid
+value and call `#age`.
+
+Finally, fill in the `name`, `color`, and `sex` fields with valid values and try
+to `save!` again. Did it work this time? Congratulations!
+
+[date-docs]: https://ruby-doc.org/stdlib-3.1.1/libdoc/date/rdoc/Date.html
+[custom validations]: https://guides.rubyonrails.org/active_record_validations.html#custom-methods
+[time-ago]:
+  http://api.rubyonrails.org/classes/ActionView/Helpers/DateHelper.html#method-i-time_ago_in_words
+[limit-docs]:
+  https://api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/SchemaStatements.html#method-i-add_column
+
+### Routes and controller
+
+Build the routes and controller as follows:
+
+* Use the `resources` keyword to create all the RESTful routes for your `Cat`
+  resource except `destroy`.
+* Set the root path (`\`) to go to your `cats#index`. (Check out the comments
+  that Rails provides in your __routes.rb__ file if you don't know how to do
+  this.)
+* Create a `CatsController` and build out the six required actions. (Again, skip
+  `destroy`.)
+* Define a private `cat_params` helper method to aid with mass assignments.
+
+### `index`/`show` pages
+
+Build an `index` page of all `Cat`s. Keep it simple: just list the cats and link
+to their show pages.
+
+Then build a `show` page for a single `Cat`. Again, keep it simple: just show
+the `Cat`'s attributes. Use a [table] (`table`, `tr`, `td`, `th` tags) to format
+the `Cat`'s vital information.
+
+[table]: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/table
+
+### `new` form
+
+Build a `new` form page to create a new `Cat`:
+
+* Use `text` for name.
+* Use radio buttons for sex.
+* Use a dropdown for color (hint: keep your code DRY by using the constant you
+  defined on the `Cat` class).
+* Use a blank `<option>` as the default color. You may want to add the text '--
+  select a color --' (or similar) so users know what this dropdown is for. This
+  will force the user to consciously pick a color.
+* You can use the `date` input type to prompt the user to pick a birth date.
+  Look this up on MDN.
+* Use a `textarea` tag for the description.
+
+### `edit` form
+
+Build an `edit` form to update a `Cat`:
+
+* Copy your `new` form to an `edit` view.
+* You'll want to make a `PATCH` request, but for historical reasons, a `<form>`
+  won't let you specify a `method` of `PATCH`.
+  * The Rails solution is to upload a special parameter `name`d `_method` with
+    the value set to the HTTP method you want.
+  * Use a hidden field to do this.
+  * We say that you are _emulating_ a `PATCH` request this way.
+* Pre-fill the form with the `Cat`'s current details.
+  * You'll use the `value` attribute a lot. You may also use the `checked` (for
+    `radio`, `checkbox`) and `selected` (for `option`) attributes.
+  * You can look up `input` and `option` attributes on MDN. It will explain
+    `checked` and `selected`.
+  * Note that `textarea` is not a self-closing tag. The value is the body of the
+    tag.
+
+### Unify!
+
+Your `edit` view duplicates your `new` view. Go ahead and unify the two:
+
+* Copy your `edit` view to a partial named `_form`.
+* Change all occurrences of the instance variable `@cat` to the local variable
+  `cat`. You will pass in the value for this local variable from the form
+  invoking the partial.
+  * You do not want to use instance variables in your partials because it would
+    promote **coupling** between your partial and the controllers that render
+    it. By passing in the instance variable as a local variable, you keep your
+    code DRY and prevent bugs should you ever decide to refactor.
+  * Using local variables also gives you the flexibility to pass different
+    variables depending on the context. For instance, you could pass
+    `@cats[idx]` if you were to use this partial in the `index` view.
+* Change your `edit` view to render the partial, passing in `@cat` as a local
+  variable named `cat` like so:
+  
+  ```rb
+  <%= render 'form', cat: @cat %>
+  ```
+
+* Test that everything still works. Yea!
+
+Your next goal is to reuse this partial for the `new` form too. To do this, you
+need to address four crucial differences between the `edit` and the `new`
+forms:
+
+  1. The `edit` form uses an existing `Cat`'s values to pre-fill the fields; the
+     `new` form doesn't have access to an existing `Cat`.
+  2. The `edit` form posts to `cat_url(cat)`; the `new` form posts to
+     `cats_url`.
+  3. The `edit` form makes a `PATCH` request; the `new` form makes a `POST`
+     request.
+  4. The `edit` form needs an `Update` button; the `new` form needs a `Create`
+     button.
+
+To resolve these differences, go back to the `new` action in your controller.
+Create--but don't save to the database!--a blank `Cat` object and assign it to
+`@cat`. Then in your `new` form, pass this `@cat` to the partial as `cat`.
+Voilà! Now the partial will pre-fill with blank values when invoked from `new`,
+exactly what you want.
+
+This blank `cat` from the `new` form can also help resolve the three other
+differences. Use [`#persisted?`][persisted] to determine which action, method,
+and button text the partial should use. When you finish making these adjustments
+to the partial, test it to make sure both forms display and behave correctly.
+
+Congratulations! You have just built a website to store and display information
+about cats. Commit your files, then move on to implementing the cat rental
+requests in [Phase II!](README-ph2.md)
+
+[persisted]: https://api.rubyonrails.org/classes/ActiveRecord/Persistence.html#method-i-persisted-3F
\ No newline at end of file
diff --git a/rails/projects/ninety_nine_cats_ii b/rails/projects/ninety_nine_cats_ii
new file mode 160000
index 0000000..ba99429
--- /dev/null
+++ b/rails/projects/ninety_nine_cats_ii
@@ -0,0 +1 @@
+Subproject commit ba99429a80c4f7b40062559fd890f40e55488b2e
diff --git a/rails/projects/reddit_on_rails/.gitattributes b/rails/projects/reddit_on_rails/.gitattributes
new file mode 100644
index 0000000..31eeee0
--- /dev/null
+++ b/rails/projects/reddit_on_rails/.gitattributes
@@ -0,0 +1,7 @@
+# See https://git-scm.com/docs/gitattributes for more about git attribute files.
+
+# Mark the database schema as having been generated.
+db/schema.rb linguist-generated
+
+# Mark any vendored files as having been vendored.
+vendor/* linguist-vendored
diff --git a/rails/projects/reddit_on_rails/.gitignore b/rails/projects/reddit_on_rails/.gitignore
new file mode 100644
index 0000000..a64aab2
--- /dev/null
+++ b/rails/projects/reddit_on_rails/.gitignore
@@ -0,0 +1,26 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore pidfiles, but keep the directory.
+/tmp/pids/*
+!/tmp/pids/
+!/tmp/pids/.keep
+
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
diff --git a/rails/projects/reddit_on_rails/README-bonus.md b/rails/projects/reddit_on_rails/README-bonus.md
new file mode 100644
index 0000000..aa51731
--- /dev/null
+++ b/rails/projects/reddit_on_rails/README-bonus.md
@@ -0,0 +1,169 @@
+# Reddit On Rails (Bonus)
+
+* [Project Demo]
+* [Actual Reddit]
+
+[Project Demo]: https://aa-reddit-app.herokuapp.com/
+[Actual Reddit]: https://www.reddit.com
+
+## Bonus I: Votes
+
+A major feature of Reddit is the ability to upvote/downvote posts and comments.
+Write a `Vote` model which allows users to vote on posts or comments. Because
+a `Vote` can be for one of two kinds of things, you'll want to use a polymorphic
+association for this.
+
+Write a `Vote` model with a `value` attribute, which should be either `+1` or
+`-1`. Add a polymorphic association `Vote#votable`. Also add `votes`
+associations to both `Post` and `Comment`.
+
+On the `SubsController#show` page, add up/downvote buttons for each post; add
+up/downvote buttons for each comment on the `PostsController#show` page. Add the
+appropriate `upvote` and `downvote` custom member routes for POST requests to
+`posts` and `comments`, e.g., `/posts/123/upvote` and `/comments/123/downvote`.
+
+Finally, sort the posts on the `SubsController#show` page by score; likewise,
+sort each level of comments by score.
+
+## Bonus II: Scopes
+
+How did you sort the posts and comments by score? Did you use a Ruby method like
+`sort` or `sort_by`? That will work, but that kind of calculation is exactly
+what databases do well. It will accordingly be more efficient to have the
+database return the posts and comments already sorted by score instead of
+sorting by score in Ruby with a Ruby method. You can do this by using [scopes]
+on the appropriate `has_many` associations.
+
+Before implementing this bonus, refresh a few post- and comment-heavy pages
+several times. Look at your server log to see how many times you are hitting the
+database for each refresh, and how long each page takes on average. This is your
+baseline that you are trying to improve.
+
+### Sorting results
+
+Scopes provide a way of customizing a query. You define scope blocks using the
+`-> {}` syntax immediately after the name of your association, like this:
+
+```rb
+has_many :posts, -> { ... }, dependent: :destroy
+```
+
+Inside the `{ }`s, you can use any of the normal Active Record [querying
+methods]: `where`, `includes`, `joins`, `select`, `group`, `order`, and so on.
+For example, the following scope block:
+
+```rb
+class Sub < ApplicationRecord
+  has_many :posts, -> { where(author: User.first) }, dependent: :destroy
+end
+```
+
+will cause `Sub#posts` to return only the posts authored by the first `User`.
+
+The query you need is a bit more complicated. Essentially, you want to construct
+a query that will return the posts sorted by the sum of the values stored for
+each post on the `votes` table. Here are a few things to keep in mind as you
+think about how to construct your query:
+
+* You will need to join the `posts` table to the `votes` table, but consider
+  carefully what kind of `join` you want. What are your options, and how will
+  the results differ with each?
+
+* Posts that have no votes will have a score of `NULL`, which PostgreSQL
+  considers to be larger than any non-`NULL` value. So if you sort in descending
+  order, the posts with no votes will all appear first. In other words, posts
+  with an effective score of 0 will appear ahead of those with higher scores. To
+  address this issue, consider using [`COALESCE`].
+
+* If you get this error:
+
+  ```text
+  Dangerous query method (method whose arguments are used as raw SQL) called with non-attribute argument(s)
+  ```
+
+  you are likely passing a potentially unsafe SQL string to your database to
+  run. Rails is concerned that the string may leave you open to a SQL injection
+  attack. If you are sure your string is safe to run--if it does not incorporate
+  any user input, you are probably good!--you can eliminate this error by
+  wrapping the string with [`Arel.sql()`]. (`Arel.sql()` essentially tells Rails
+  that you know what you are doing; Rails will accordingly stop worrying about
+  the string and just run it.)
+
+Once you get your scope working for posts, add a similar scope to
+`Post#comments`.
+
+### Counting votes
+
+You probably have a method for counting a `votable`'s vote score that involves
+summing the values of the `votable`'s votes. This method also likely results in
+several queries to your database. This is wasteful, especially since your
+`has_many` associations now have the database perform that exact calculation.
+Once you've done a calculation, there's no reason to keep querying the database
+to calculate it again.
+
+The challenge is how to capture the vote score that the associations calculate.
+After all, you don't have (and don't need to have) an extra `votes` column on
+your `posts` or `comments` table. But there's no reason you can't store the
+information in a local variable...
+
+To achieve this, you need PostgreSQL to store the calculated value in a named
+column that will be returned as part of the result. (Hint: use `AS`.) That named
+column will not show up if you examine the returned `posts`/`comments` because
+it is not part of their models. But it is there. So, e.g., if you name the
+column `num_votes` then you should be able to do this:
+
+```rb
+[1] pry(main)> comment = Post.first.comments.first
+  # ... SQL Query hidden :) ...
+=> #<Comment:0x00000001108fe290
+ id: 1,
+ body: "Not me...",
+ parent_comment_id: nil,
+ post_id: 1,
+ author_id: 1,
+ created_at: Thu, 30 Jun 2022 17:54:32.426599000 UTC +00:00,
+ updated_at: Thu, 30 Jun 2022 17:54:32.426599000 UTC +00:00>
+[2] pry(main)> comment.num_votes
+=> 2
+```
+
+Once you get this set up correctly, you can return this value from your method
+that counts votes, no further database querying needed!
+
+A couple caveats:
+
+1. It is likely that your vote-counting method will be called at times from a
+   post/comment that has not been generated from your `has_many` scopes. You
+   need to account for that case.
+
+2. Trying to access `post.num_votes` if `num_votes` is not defined will crash
+   your program. You may accordingly find [this method][defined?] helpful.
+
+When you finish, refresh the same pages that you did at the beginning of this
+bonus and check the server logs. How do the database hits and average time
+compare?
+
+## Ideas for future enhancements
+
+* Use the [Friendly ID][friendly-id] gem to use human readable names in urls for
+  posts and subs.
+* Use the [kaminari] gem to paginate posts on the `SubsController#show` page.
+* Enable users to subscribe to specific `subs` and only see `posts` from those
+  `subs` on the `index` page.
+* Enable users to search for any `sub`, including ones they aren't subscribed
+  to.
+* Have the user `show` page display all of a user's `posts`, `comments`, and the
+  total number of `votes` they've received from other people for their `posts`
+  and `comments`.
+* Add lots of seeds with [Faker][faker].
+* Style your Reddit app! Try to make it look as much like actual Reddit as you
+  can.
+
+[querying methods]: https://guides.rubyonrails.org/active_record_querying.html#retrieving-objects-from-the-database
+[scopes]: https://guides.rubyonrails.org/association_basics.html#scopes-for-has-many
+[`COALESCE`]: https://www.postgresql.org/docs/current/functions-conditional.html#FUNCTIONS-COALESCE-NVL-IFNULL
+[`Arel.sql()`]: https://api.rubyonrails.org/classes/Arel.html
+[defined?]: https://ruby-doc.org/docs/keywords/1.9/Object.html#method-i-defined-3F
+[faker]: https://github.com/stympy/faker
+[kaminari]: https://github.com/amatsuda/kaminari
+[friendly-id]: https://github.com/norman/friendly_id
diff --git a/rails/projects/reddit_on_rails/README-ph4-6.md b/rails/projects/reddit_on_rails/README-ph4-6.md
new file mode 100644
index 0000000..5972712
--- /dev/null
+++ b/rails/projects/reddit_on_rails/README-ph4-6.md
@@ -0,0 +1,159 @@
+# Reddit On Rails (Phases IV-VI)
+
+* [Project Demo]
+* [Actual Reddit]
+
+[Project Demo]: https://aa-reddit-app.herokuapp.com/
+[Actual Reddit]: https://www.reddit.com
+
+## Phase IV: `Comment`
+
+Users should be allowed to write a `Comment`. There are two kinds of comments:
+
+* Top-level comments that are in direct response to the `Post`
+* Nested comments that respond to a `Comment`
+
+Start by focusing on top-level comments. Write a `Comment` model with:
+
+* A `body` attribute
+* An `author` association
+* A `post` association
+
+Create `CommentsController` and a top-level `create` route. Also create a `new`
+route nested under `posts` (should look like: `/posts/:post_id/comments/new`).
+These are the only two comment routes you need so far.
+
+Edit your `PostsController#show` view to provide a link to a comment form and to
+display top-level comments.
+
+### Nested comments
+
+Start allowing nested comments. To do this, add a self-referencing foreign
+key `parent_comment_id` to `Comment`. Top-level comments will have a `NULL`
+`parent_comment_id`, but nested comments should store a reference to their
+parent. **Nested-comments should still store a `post_id`, even though this may
+seem redundant**; you'll see why later. Write a `Comment#child_comments`
+association. Write a `Post#comments` association.
+
+Note that Rails automatically validates `belongs_to` associations, so
+you'll need to pass `optional: true` when you want to allow for `nil` foreign
+keys.
+
+On your `PostsController#show` page, for each top level comment, add a link to
+the `show` page of the comment (e.g., to `/comments/123`). You can find top
+level comments like so: `@post.comments.where(parent_comment_id: nil)`.
+
+Even though the comment is visible on the `Post` `show` page, add a link to a
+`Comment` `show` page at `/comments/123`. This page will give you a good place
+to show not only the specific comment, but also a form to reply to this comment.
+To repeat, this is how you're going to support nested replies: the user clicks a
+link to the comment show page, which has a form to write the nested reply.
+
+On the `Comment` show page, have a form that, when posted, will create the
+**nested** comment. This is in addition to your comment form on the `Post`
+`show` page at `/posts/456`, which makes new **top-level** comments. Both forms
+should post to `/comments`.
+
+Update your `PostsController#show` to display nested comments too. Use nested
+`ul` tags to make the parent-child relationship obvious.
+
+Build a `_comment` partial to display a `comment` and have the partial
+iterate through the `#child_comments`, recursively rendering the partial for
+each nested comment.
+
+**This is an N+1 query approach**. This approach will first query all top-level
+comments with `Post#top_level_comments`. Then, for each top-level `Comment`, the
+partial will call `child_comments` to get the second-level comments. For each
+second-level comment, the recursive partial call will call `child_comments`
+again to get the third-level comments...
+
+`Comment#child_comments` gets called once per comment, so this is N+1.
+
+**You'll fix this soon**, but get the N+1 way working first!
+
+## Phase V: Comments Without N+1 Queries
+
+Instead of fetching comments over-and-over again, you can fetch **all** the
+comments you'll need at once by writing a plain `Post#comments` association.
+This includes both top-level comments and all the nested comments.
+
+Fetching all the comments this way creates some difficulty because it doesn't
+organize the comments in an easy-to-access parent-child relationship. Have the
+`PostsController#show` fetch all the comments for a post and store them in an
+instance variable `@all_comments`. In the view, iterate through `@all_comments`
+and skip those where `parent_comment_id IS NOT NULL`; render the `_comment`
+partial only for the top-level comments.
+
+The `_comment` partial renders a comment (let's call it `c1`). It should display
+the `c1.body`, `c1.author.username`, and `c1.created_at`. As before, it needs
+to display the comments that are replying to `c1`. Previously, you wrote
+`c1.comments` to get these second-level comments. However, that would trigger a
+second query.
+
+You've already fetched the second-level comments (along with many others) and
+stored them in `@all_comments`. So instead of calling `c1.comments`, do an
+`@all_comments.each do |c2|` and recursively render the `_comment` partial
+**only** when `c2.parent_comment_id == c1.id`. Because `@all_comments` contains
+all the comments for the `Post` at every level, you won't miss any of
+`c1#child_comments`.
+
+One quick note: calling `comment#author` repeatedly will also trigger an N+1
+query, so use `includes(:author)` when fetching `@all_comments`.
+
+## Phase VI: Even Faster Comments
+
+For each comment, to find all child comments, our approach iterates through the
+entire `@all_comments` array. This approach is slow:
+
+* Say there are 1000 comments overall.
+* For each of the 1000 comments `c1`, you'll iterate through all 1000 comments,
+  checking `c1.id == c2.parent_comment_id` each time.
+* This is a total of `1000 * 1000 == 1MM` comparisons.
+
+This is an `O(n**2)` algorithm. The time it takes to render the comments will
+grow proportional to the square of the number of comments. You can change the
+approach to an `O(n)` algorithm where the time to render comments grows linearly
+with the total number of comments.
+
+The obvious waste of the former approach is that you iterate through
+`@all_comments` repeatedly to find child comments. Instead, after fetching all
+the comments for a post, write a method `Post#comments_by_parent_id` which
+returns a **hash** of comments, where the keys are parent comment ids, and the
+values are children comments:
+
+```ruby
+post.comments
+# => [
+#   { id: 1, parent_comment_id: nil, body: "top-level-1" },
+#   { id: 2, parent_comment_id: nil, body: "top-level-2" },
+#   { id: 3, parent_comment_id: 1, body: "nested-1" },
+#   { id: 4, parent_comment_id: 3, body: "nested-2" },
+#   { id: 5, parent_comment_id: 3, body: "nested-3" }
+# ]
+
+@comments_by_parent_id = post.comments_by_parent_id
+# => {
+#   nil => [
+#     { id: 1, parent_comment_id: nil, body: "top-level-1" },
+#     { id: 2, parent_comment_id: nil, body: "top-level-2" }
+#   ],
+#
+#   1 => [
+#     { id: 3, parent_comment_id: 1, body: "nested-1" }
+#   ],
+#
+#   3 => [
+#     { id: 4, parent_comment_id: 3, body: "nested-2" },
+#     { id: 5, parent_comment_id: 3, body: "nested-3" }
+#   ]
+# }
+```
+
+If you have a hash like this, it becomes very fast to find child comments of
+`c1`: `@comments_by_parent_id[c1.id]`. It turns out that hash lookup is
+insensitive to the size of the hash (it is `O(1)`).
+
+Write `Post#comments_by_parent_id`, call it in the controller and set an
+instance variable, then use it in your `_comment` partial.
+
+Next up: [Bonuses](README-bonus.md) for setting up votes and using association scopes!
diff --git a/rails/projects/reddit_on_rails/README.md b/rails/projects/reddit_on_rails/README.md
new file mode 100644
index 0000000..248ba16
--- /dev/null
+++ b/rails/projects/reddit_on_rails/README.md
@@ -0,0 +1,86 @@
+# Reddit On Rails
+
+* [Project Demo]
+* [Actual Reddit]
+
+[Project Demo]: https://aa-reddit-app.herokuapp.com/
+[Actual Reddit]: https://www.reddit.com
+
+## Learning goals
+
+* Be able to write auth from scratch without looking at previous solutions
+* Know how to use a `before_action` to manage user access to resources
+* Be able to write Rails models, controllers, and views quickly
+* Know when to use regular associations and when to use join tables
+* Know how to avoid N+1 queries
+
+## Quick review
+
+This is the last Rails project before building Rails Lite yourself tomorrow.
+Take a few minutes to talk through the whole request/response cycle with your
+partner before getting started. Feel free to reference this diagram as needed.
+
+[Rails Diagram](https://assets.aaonline.io/fullstack/rails/assets/rails_diagram.png)
+
+## Phase I: Auth
+
+Write a basic Auth implementation (`User`, `UsersController`,
+`SessionsController`).
+
+**Do not look at previous days' solutions.  Write Auth from scratch!**  It is
+important that you understand how each method works, and how to debug any errors
+you may encounter.  
+
+## Phase II: `Sub` and `Post`
+
+A `Sub` is a topic-specific sub-forum to which users submit a `Post`. Start by
+writing a `Sub` model and `SubsController`. The `Sub` should have `title` and
+(optional) `description` attributes and a `moderator` association. The creator
+of the `Sub` is the `moderator`.
+
+Write all the standard seven routes for `SubsController`. You can leave out
+`destroy` if you'd like.
+
+Write an `edit` route where the moderator is allowed to update the `title` and
+`description`. Use a `before_action` to prohibit non-moderators from editing or
+updating the `Sub`.
+
+The point of a `Sub` is for users to share posts. A `Post` should consist of:
+
+* A `title` attribute (required)
+* A `url` attribute (optional)
+* A `content` attribute for content text (optional)
+* A `sub` association to the `Sub` the `Post` is submitted to (required)
+* An `author` association
+
+Again, write all the standard `PostsController` actions, except for `index` (the
+`subs#show` can list `posts`). (Again, you can skip `destroy`.)
+
+Write `posts#edit` and `posts#update` controller actions (and routes) that only
+the `Post` author can use.
+
+## Phase III: Cross-posting to multiple `Sub`s
+
+Allow a `Post` to be posted to multiple subs. This will involve a `PostSub` join
+table to describe the many-to-many relationship. Add appropriate DB constraints
+and model validations to `PostSub`. Require that a `Post` has at least one
+associated sub. Create appropriate associations between `Post`, `PostSub`, and
+`Sub`.
+
+Edit your `Post` `new`/`edit` views to allow the user to select multiple subs
+via checkboxes.
+
+* Structure your HTML form to upload an array of `sub_ids` nested under `post`
+* Update the `PostsController#post_params` to accept an array of `sub_ids`
+
+You should now be able to associate a post with the subs that you select. This
+works because the `Post#subs` association gives you a method, `Post#sub_ids=`,
+that will automatically create/destroy the necessary entries in the `PostSub`
+join table. Recall that Rails will call a setter method for each attribute that
+you assign in `Post.new` or `Post#update`, so if one of the keys in your
+attributes hash is `sub_ids`, Rails will automatically call `Post#sub_ids=`.
+
+Lastly, make sure your form can be edited. Use the boolean `checked` HTML
+attribute.
+
+When you finish, head on to [Phase IV!](README-ph4-6.md)
diff --git a/rails/quizzes/auth.md b/rails/quizzes/auth.md
index b3ff324..94d5998 100644
--- a/rails/quizzes/auth.md
+++ b/rails/quizzes/auth.md
@@ -1,44 +1,50 @@
 # Rails Auth
 
-<quiz>
-  <question >
-  <p>Which of the following statements about cookies are true? They are ...</p>
-    <answer>Stored on the server.</answer>
-    <answer correct>Uploaded with every HTTP request.</answer>
-    <answer>Safe from attacks.</answer>
-    <explanation>Cookies are stored with the client's browser and are therefore not safe from attack!</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question >
-  <p>T/F: Model instances get destroyed after an HTTP response has been sent by Rails.</p>
-    <answer correct>True</answer>
-    <answer>False</answer>
-    <explanation>True! With the end of each HTTP response all model instances are destroyed.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question multiple>
-  <p>Which of the following statements about `Flash` and `Flash.now` are true? (Select all that apply.)</p>
-    <answer correct>`Flash` is accessible during the next request; `Flash.now` is accessible only during the current request</answer>
-    <answer>`Flash.now` is accessible during the next request; `Flash`is accessible only during the current request</answer>
-    <answer correct>`Flash`is usually used with redirects while `Flash.now` is usually used with renders</answer>
-    <answer>`Flash.now` is usually used with redirects while `Flash`is usually used with renders</answer>
-    <explanation>`Flash` is accessible during the next request which is why you use it with redirects. `Flash.now` is accessible during the current request which is why you use it with `render`.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>What is a CSRF attack?</p>
-    <answer>A Cross-Site Response Fraud attack in which a form fails to submit correctly</answer>
-    <answer correct>A Cross-Site Request Forgery attack in which one site holds a form that acts on another site's server</answer>
-    <answer>A Cross-Site Response Forgery attack in which a form is submitted multiple times from a single click</answer>
-    <explanation>A CSRF attack is when one site holds a form that acts on another site's server. One site would be creating a *request forgery* to another site.</explanation>
-  </question>
-</quiz>
+Which of the following statements about cookies are true? They are ...
+- [ ] Stored on the server.
+- [ ] Uploaded with every HTTP request.
+- [ ] Safe from attacks.
+
+<details><summary>Answer:</summary>
+Uploaded with every HTTP request.</details>
+<details><summary>Explanation:</summary>
+
+Cookies are stored with the client's browser and are therefore not safe from attack!</details>
+
+T/F: Model instances get destroyed after an HTTP response has been sent by Rails.
+- [ ] True
+- [ ] False
+
+<details><summary>Answer:</summary>
+True</details>
+<details><summary>Explanation:</summary>
+
+True! With the end of each HTTP response all model instances are destroyed.</details>
+
+Which of the following statements about `Flash` and `Flash.now` are true? (Select all that apply.)
+- [ ] `Flash` is accessible during the next request; `Flash.now` is accessible only during the current request
+- [ ] `Flash.now` is accessible during the next request; `Flash`is accessible only during the current request
+- [ ] `Flash`is usually used with redirects while `Flash.now` is usually used with renders
+- [ ] `Flash.now` is usually used with redirects while `Flash`is usually used with renders
+
+<details><summary>Answer:</summary>
+
+- `Flash` is accessible during the next request; `Flash.now` is accessible only during the current request
+- Flash`is usually used with redirects while `Flash.now` is usually used with renders</details>
+<details><summary>Explanation:</summary>
+
+`Flash` is accessible during the next request which is why you use it with redirects. `Flash.now` is accessible during the current request which is why you use it with `render`.</details>
+
+What is a CSRF attack?
+- [ ] A Cross-Site Response Fraud attack in which a form fails to submit correctly
+- [ ] A Cross-Site Request Forgery attack in which one site holds a form that acts on another site's server
+- [ ] A Cross-Site Response Forgery attack in which a form is submitted multiple times from a single click
+
+<details><summary>Answer:</summary>
+A Cross-Site Request Forgery attack in which one site holds a form that acts on another site's server</details>
+<details><summary>Explanation:</summary>
+
+A CSRF attack is when one site holds a form that acts on another site's server. One site would be creating a *request forgery* to another site.</details>
 
 ```html
 <input
@@ -47,14 +53,14 @@
   value="<% form_authenticity_token %>"
 />
 ```
+What is wrong with the above code?
+- [ ] The input type should be `text` instead of `hidden`.
+- [ ] The name should be `form_authenticity_token` and the value should be `authenticity_token`.
+- [ ] It uses incorrect ERB tags for the value attribute.
+- [ ] The input needs a label surrounding it.
+
+<details><summary>Answer:</summary>
+It uses incorrect ERB tags for the value attribute.</details>
+<details><summary>Explanation:</summary>
 
-<quiz>
-  <question>
-  <p>What is wrong with the above code?</p>
-    <answer>The input type should be `text` instead of `hidden`.</answer>
-    <answer>The name should be `form_authenticity_token` and the value should be `authenticity_token`.</answer>
-    <answer correct>It uses incorrect ERB tags for the value attribute.</answer>
-    <answer>The input needs a label surrounding it.</answer>
-    <explanation>If you want the value to be returned, you need to use printing ERB tags (`<%= %>`)</explanation>
-  </question>
-</quiz>
+If you want the value to be returned, you need to use printing ERB tags (`<%= %>`)</details>
diff --git a/rails/quizzes/css.md b/rails/quizzes/css.md
index 3de0b64..643003d 100644
--- a/rails/quizzes/css.md
+++ b/rails/quizzes/css.md
@@ -1,15 +1,17 @@
 # CSS
 
-<quiz>
-  <question>
-  <p>Which of the following does **NOT** belong in the HTML `head` section?</p>
-    <answer>`meta` tags</answer>
-    <answer>`script` tags</answer>
-    <answer correct>a `navbar`</answer>
-    <answer>`link` tags to load in CSS</answer>
-    <explanation>A `navbar` belongs within the `body` tag.</explanation>
-  </question>
-</quiz>
+Which of the following does **NOT** belong in the HTML `head` section?
+- [ ] `meta` tags
+- [ ] `script` tags
+- [ ] a `navbar`
+- [ ] `link` tags to load in CSS
+
+<details><summary>Answer:</summary>
+
+a `navbar`</details>
+<details><summary>Explanation:</summary>
+
+A `navbar` belongs within the `body` tag.</details>
 
 ```html
 <!-- Think back on the rules for selector precedence and consider the following: -->
@@ -33,16 +35,18 @@
 </p>
 ```
 
-<quiz>
-  <question>
-  <p>What will be the `font-size` and `color` of the text?</p>
-    <answer correct>`color: yellow`, `font-size: 80px`</answer>
-    <answer>`color: red`, `font-size: 80px`</answer>
-    <answer>`color: yellow`, `font-size: 12px`</answer>
-    <answer>`color: red`, `font-size: 12px`</answer>
-    <explanation>The `id` attribute takes precedence over the other attributes, so the `#big` CSS rule would ensure the `font-size: 80px`. Then the specificity of the `span` tag inheriting from the `p` tag would ensure the `color` would be `yellow`.</explanation>
-  </question>
-</quiz>
+What will be the `font-size` and `color` of the text?
+- [ ] `color: yellow`, `font-size: 80px`
+- [ ] `color: red`, `font-size: 80px`
+- [ ] `color: yellow`, `font-size: 12px`
+- [ ] `color: red`, `font-size: 12px`
+
+<details><summary>Answer:</summary>
+
+`color: yellow`, `font-size: 80px`</details>
+<details><summary>Explanation:</summary>
+
+The `id` attribute takes precedence over the other attributes, so the `#big` CSS rule would ensure the `font-size: 80px`. Then the specificity of the `span` tag inheriting from the `p` tag would ensure the `color` would be `yellow`.</details>
 
 ```html
 <!-- Think back on the rules for selector precedence and consider the following: -->
@@ -67,15 +71,17 @@
 </article>
 ```
 
-<quiz>
-  <question>
-  <p>What will be the `color` of the text?</p>
-    <answer>red</answer>
-    <answer correct>yellow</answer>
-    <answer>blue</answer>
-    <explanation>Precedence wins again! Since both the `section` and the `p` tag inherit from the `article` tag then the color of the text will be `yellow`. </explanation>
-  </question>
-</quiz>
+What will be the `color` of the text?
+- [ ] red
+- [ ] yellow
+- [ ] blue
+
+<details><summary>Answer:</summary>
+
+yellow</details>
+<details><summary>Explanation:</summary>
+
+Precedence wins again! Since both the `section` and the `p` tag inherit from the `article` tag then the color of the text will be `yellow`. </details>
 
 ```html
 <!-- Consider the following: -->
@@ -96,17 +102,19 @@
 <p>Third Paragraph</p>
 ```
 
-<quiz>
-  <question>
-  <p>Let's make the paragraphs display with 10 pixels of white space between them. What should the above `margin` and `padding` properties be set to?</p>
-    <answer>`margin: 5px`, `padding: 0`</answer>
-    <answer>`margin: 5px`, `padding: 5px`</answer>
-    <answer>`margin: 5px`, `padding: 10px`</answer>
-    <answer correct>`margin: 10px`, `padding: 0`</answer>
-    <answer>`margin: 0px`, `padding: 10px`</answer>
-    <explanation>For this problem you just need margin! Try experimenting with the different answers to see why.</explanation>
-  </question>
-</quiz>
+Let's make the paragraphs display with 10 pixels of white space between them. What should the above `margin` and `padding` properties be set to?
+- [ ] `margin: 5px`, `padding: 0`
+- [ ] `margin: 5px`, `padding: 5px`
+- [ ] `margin: 5px`, `padding: 10px`
+- [ ] `margin: 10px`, `padding: 0`
+- [ ] `margin: 0px`, `padding: 10px`
+
+<details><summary>Answer:</summary>
+
+`margin: 10px`, `padding: 0`</details>
+<details><summary>Explanation:</summary>
+
+For this problem you just need margin! Try experimenting with the different answers to see why.</details>
 
 ```html
 <!-- Consider the following: -->
@@ -122,16 +130,19 @@
 <section>I AM ALSO A SECTION</section>
 ```
 
-<quiz>
-  <question multiple>
-  <p>You want the `section`s to appear next to each other, and for each `section` to be `100px` tall and `100px` wide. Which of the following properties could you add to the `section` styling to achieve this? (Select all that apply.)</p>
-    <answer>`display: inline`</answer>
-    <answer correct>`display: inline-block`</answer>
-    <answer correct>`float: left`</answer>
-    <answer>None of these answers</answer>
-    <explanation>Both `display: inline-block` and `float: left` could achieve the look you are after!</explanation>
-  </question>
-</quiz>
+You want the `section`s to appear next to each other, and for each `section` to be `100px` tall and `100px` wide. Which of the following properties could you add to the `section` styling to achieve this? (Select all that apply.)
+- [ ] `display: inline`
+- [ ] `display: inline-block`
+- [ ] `float: left`
+- [ ] None of these answers
+
+<details><summary>Answer:</summary>
+
+- `display: inline-block`
+- `float: left`</details>
+<details><summary>Explanation:</summary>
+
+Both `display: inline-block` and `float: left` could achieve the look you are after!</details>
 
 ```html
 <!-- Consider the following: -->
@@ -147,13 +158,15 @@
 </p>
 ```
 
-<quiz>
-  <question>
-  <p>What will be the `p` tag's color and font size?</p>
-    <answer>`red`, `16px`</answer>
-    <answer>`red`, `12px`</answer>
-    <answer correct>`#FFFFFF`, `12px` </answer>
-    <answer>`#FFFFFF`, `16px`</answer>
-    <explanation>Inline styling will always be the most specific and will override any other CSS rule.</explanation>
-  </question>
-</quiz>
+What will be the `p` tag's color and font size?
+- [ ] `red`, `16px`
+- [ ] `red`, `12px`
+- [ ] `#FFFFFF`, `12px` 
+- [ ] `#FFFFFF`, `16px`
+
+<details><summary>Answer:</summary>
+
+`#FFFFFF`, `12px` </details>
+<details><summary>Explanation:</summary>
+
+Inline styling will always be the most specific and will override any other CSS rule.</details>
diff --git a/rails/quizzes/rails_forms.md b/rails/quizzes/rails_forms.md
index 3a23c87..4edd7a8 100644
--- a/rails/quizzes/rails_forms.md
+++ b/rails/quizzes/rails_forms.md
@@ -4,15 +4,17 @@
 <input type='hidden' name='cat[tag_ids][]' value=''>
 ```
 
-<quiz>
-  <question>
-  <p>What is the purpose of the above line of code?</p>
-    <answer>To set the 'tag_ids' to all available tags, the default value.</answer>
-    <answer>To prevent any 'tag_ids' from being displayed on the page.</answer>
-    <answer correct>To ensure 'tag_ids' is set to an empty array even if nothing was selected.</answer>
-    <explanation>To ensure that 'tag_ids' sends an empty array even if no selection was made, you can set the `name` to `cat[tag_ids][]`. </explanation>
-  </question>
-</quiz>
+What is the purpose of the above line of code?
+- [ ] To set the 'tag_ids' to all available tags, the default value.
+- [ ] To prevent any 'tag_ids' from being displayed on the page.
+- [ ] To ensure 'tag_ids' is set to an empty array even if nothing was selected.
+
+<details><summary>Answer:</summary>
+
+To ensure 'tag_ids' is set to an empty array even if nothing was selected.</details>
+<details><summary>Explanation:</summary>
+
+To ensure that 'tag_ids' sends an empty array even if no selection was made, you can set the `name` to `cat[tag_ids][]`. </details>
 
 ```ruby
 # Consider the following code:
@@ -29,15 +31,17 @@ def index
 end
 ```
 
-<quiz>
-  <question>
-  <p>What will a GET request to `/cats?cat_name=Markov` result in?</p>
-    <answer correct>A list of all the cats.</answer>
-    <answer>Only the cats named 'Markov'.</answer>
-    <answer>An error.</answer>
-    <explanation>Since there is no `tag` parameter being passed in, the above request will produce a list of all the cats.</explanation>
-  </question>
-</quiz>
+What will a GET request to `/cats?cat_name=Markov` result in?
+- [ ] A list of all the cats.
+- [ ] Only the cats named 'Markov'.
+- [ ] An error.
+
+<details><summary>Answer:</summary>
+
+A list of all the cats.</details>
+<details><summary>Explanation:</summary>
+
+Since there is no `tag` parameter being passed in, the above request will produce a list of all the cats.</details>
 
 ```ruby
 # Consider the following code:
@@ -54,34 +58,42 @@ def index
 end
 ```
 
-<quiz>
-  <question>
-  <p>What will a GET request to `/cats?tag=athletic` result in?</p>
-    <answer>A list of all the cats.</answer>
-    <answer correct>A list of all the cats tagged 'athletic'.</answer>
-    <answer> An empty list, no cats.</answer>
-    <answer> An error.</answer>
-    <explanation>This request has a `tag` parameter, so it will produce a list of all the cats tagged 'athletic'.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question multiple>
-  <p>How are concerns different from regular modules? (Select all that apply.)</p>
-    <answer correct>They can run code in the class scope at the time they are included.</answer>
-    <answer correct>They have their own dedicated folders in the default Rails folder hierarchy.</answer>
-    <answer correct>They include the line 'extend ActiveSupport::Concern'</answer>
-    <explanation>All of the above!</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>What extra key-value pair must be added to a 'belongs_to' association to enable polymorphic associative behavior?</p>
-    <answer correct>`polymorphic: true`</answer>
-    <answer>`polymorphic_key: :id`</answer>
-    <answer>`as: :polymorphic`</answer>
-    <answer>`as: :pictureable`</answer>
-    <explanation>It's as simple as marking the association `polymorphic: true`.</explanation>
-  </question>
-</quiz>
+What will a GET request to `/cats?tag=athletic` result in?
+- [ ] A list of all the cats.
+- [ ] A list of all the cats tagged 'athletic'.
+- [ ]  An empty list, no cats.
+- [ ]  An error.
+
+<details><summary>Answer:</summary>
+
+A list of all the cats tagged 'athletic'.</details>
+<details><summary>Explanation:</summary>
+
+This request has a `tag` parameter, so it will produce a list of all the cats tagged 'athletic'.</details>
+
+How are concerns different from regular modules? (Select all that apply.)
+- [ ] They can run code in the class scope at the time they are included.
+- [ ] They have their own dedicated folders in the default Rails folder hierarchy.
+- [ ] They include the line 'extend ActiveSupport::Concern'
+
+<details><summary>Answer:</summary>
+
+- They can run code in the class scope at the time they are included.
+- They have their own dedicated folders in the default Rails folder hierarchy.
+- They include the line 'extend ActiveSupport::Concern'</details>
+<details><summary>Explanation:</summary>
+
+All of the above!</details>
+
+What extra key-value pair must be added to a 'belongs_to' association to enable polymorphic associative behavior?
+- [ ] `polymorphic: true`
+- [ ] `polymorphic_key: :id`
+- [ ] `as: :polymorphic`
+- [ ] `as: :pictureable`
+
+<details><summary>Answer:</summary>
+
+`polymorphic: true`</details>
+<details><summary>Explanation:</summary>
+
+It's as simple as marking the association `polymorphic: true`.</details>
diff --git a/rails/quizzes/rails_lite.md b/rails/quizzes/rails_lite.md
index ee10d60..3494f90 100644
--- a/rails/quizzes/rails_lite.md
+++ b/rails/quizzes/rails_lite.md
@@ -1,73 +1,85 @@
 # Rails Lite
 
-<quiz>
-  <question>
-  <p>Which of the following is **NOT** part of an HTTP request?</p>
-    <answer>HTTP method</answer>
-    <answer correct>Status Code</answer>
-    <answer>Request Header</answer>
-    <answer>Request Target</answer>
-    <answer>HTTP Protocol Version</answer>
-    <explanation>The status code is the only thing not included in an HTTP request.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>Which list contains only items that the Rails framework provides for you when creating a default Rails project?</p>
-    <answer>jQuery, RSpec, The Router  </answer>
-    <answer>The Database, WEBrick, Sinatra</answer>
-    <answer>Routes, Models, Controllers, Views</answer>
-    <answer correct>Rack, Active Record Base, Action Controller, Puma</answer>
-    <answer>Active Record Base, Models, The Router, HTTP</answer>
-    <explanation>Rails only provides the Rack, Active Record Base, Action Controller, and Puma.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>Suppose you want to capture only the part of the URL that comes **before** the query string. Using Regex, what is the best way to do this?</p>
-    <answer>`/^(\?)/`</answer>
-    <answer>`/\\?\w+\=/`</answer>
-    <answer correct>`/^[^\?]*/`</answer>
-    <answer>`/\.\w+\/\w+\\?/`</answer>
-    <answer>`/http:\/\/\w+\.\w+\//`</answer>
-    <explanation>You want to match everything before the `?` in the URL. The first `^` says to start at the beginning of the string. `[^\?]` says to match any single character that is not (`^`) `?`. Finally, the `*` says to match this single-character-that-is-not-? between 0 and an unlimited number of times.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>Imagine you make a request to the Google Maps API but accidentally enter an incorrect API key. What response status would you expect to get back?</p>
-    <answer>204</answer>
-    <answer>301</answer>
-    <answer correct>401</answer>
-    <answer>404</answer>
-    <answer>418</answer>
-    <explanation>The 401 (Unauthorized) status code indicates that the request has not been applied because it lacks valid authentication credentials for the target resource.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>What does `Rack::Response#write` do? It ...</p>
-    <answer>Creates a mock GET request object from the given string.</answer>
-    <answer>Parses the given text string into an HTML request.</answer>
-    <answer>Sets the body of the request to the given string.</answer>
-    <answer>Formats stored response data into properly formatted HTTP.</answer>
-    <answer correct>Appends the given string to the body and updates Content-Length.</answer>
-    <explanation>`Rack::Response#write` appends the given string to the body and updates Content-Length.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>Which of the following is **NOT** an example of middleware?</p>
-    <answer>A static asset server</answer>
-    <answer>Request authentication</answer>
-    <answer>A server log</answer>
-    <answer>A browser filter that redirects you to download Chrome if you visit the site using IE</answer>
-    <answer correct>The main web application</answer>
-    <explanation>Middleware can do many different things, but middleware's purpose is to allow software developers to focus on the specific purpose of their application. So the main web application is **not** an example of middleware.</explanation>
-  </question>
-</quiz>
+Which of the following is **NOT** part of an HTTP request?
+- [ ] HTTP method
+- [ ] Status Code
+- [ ] Request Header
+- [ ] Request Target
+- [ ] HTTP Protocol Version
+
+<details><summary>Answer:</summary>
+
+Status Code</details>
+<details><summary>Explanation:</summary>
+
+The status code is the only thing not included in an HTTP request.</details>
+
+Which list contains only items that the Rails framework provides for you when creating a default Rails project?
+- [ ] jQuery, RSpec, The Router  
+- [ ] The Database, WEBrick, Sinatra
+- [ ] Routes, Models, Controllers, Views
+- [ ] Rack, Active Record Base, Action Controller, Puma
+- [ ] Active Record Base, Models, The Router, HTTP
+
+<details><summary>Answer:</summary>
+
+Rack, Active Record Base, Action Controller, Puma</details>
+<details><summary>Explanation:</summary>
+
+Rails only provides the Rack, Active Record Base, Action Controller, and Puma.</details>
+
+Suppose you want to capture only the part of the URL that comes **before** the query string. Using Regex, what is the best way to do this?
+- [ ] `/^(\?)/`
+- [ ] `/\\?\w+\=/`
+- [ ] `/^[^\?]*/`
+- [ ] `/\.\w+\/\w+\\?/`
+- [ ] `/http:\/\/\w+\.\w+\//`
+
+<details><summary>Answer:</summary>
+
+`/^[^\?]*/`</details>
+<details><summary>Explanation:</summary>
+
+You want to match everything before the `?` in the URL. The first `^` says to start at the beginning of the string. `[^\?]` says to match any single character that is not (`^`) `?`. Finally, the `*` says to match this single-character-that-is-not-? between 0 and an unlimited number of times.</details>
+
+Imagine you make a request to the Google Maps API but accidentally enter an incorrect API key. What response status would you expect to get back?
+- [ ] 204
+- [ ] 301
+- [ ] 401
+- [ ] 404
+- [ ] 418
+
+<details><summary>Answer:</summary>
+
+401</details>
+<details><summary>Explanation:</summary>
+
+The 401 (Unauthorized) status code indicates that the request has not been applied because it lacks valid authentication credentials for the target resource.</details>
+
+What does `Rack::Response#write` do? It ...
+- [ ] Creates a mock GET request object from the given string.
+- [ ] Parses the given text string into an HTML request.
+- [ ] Sets the body of the request to the given string.
+- [ ] Formats stored response data into properly formatted HTTP.
+- [ ] Appends the given string to the body and updates Content-Length.
+
+<details><summary>Answer:</summary>
+
+Appends the given string to the body and updates Content-Length.</details>
+<details><summary>Explanation:</summary>
+
+`Rack::Response#write` appends the given string to the body and updates Content-Length.</details>
+
+Which of the following is **NOT** an example of middleware?
+- [ ] A static asset server
+- [ ] Request authentication
+- [ ] A server log
+- [ ] A browser filter that redirects you to download Chrome if you visit the site using IE
+- [ ] The main web application
+
+<details><summary>Answer:</summary>
+
+The main web application</details>
+<details><summary>Explanation:</summary>
+
+Middleware can do many different things, but middleware's purpose is to allow software developers to focus on the specific purpose of their application. So the main web application is **not** an example of middleware.</details>
diff --git a/rails/quizzes/routes_and_controllers.md b/rails/quizzes/routes_and_controllers.md
index 1b3f0a6..172be1a 100644
--- a/rails/quizzes/routes_and_controllers.md
+++ b/rails/quizzes/routes_and_controllers.md
@@ -1,55 +1,67 @@
 # Routes and Controllers
 
-<quiz>
-  <question multiple>
-  <p>Where do the key-value pairs in the `params` hash come from? (Select all that apply.)</p>
-    <answer correct>Query string</answer>
-    <answer correct>The path of the request</answer>
-    <answer correct>Form data from a `POST`/`PATCH`/`PUT` request</answer>
-    <explanation>All of the above!</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>The server returned a blank form for creating a cat. Assuming RESTful Routes, which request was made?</p>
-    <answer>HTTP Verb: `NEW` Path: `/cats/`</answer>
-    <answer correct> HTTP Verb: `GET` Path: `/cats/new`</answer>
-    <answer>HTTP Verb: `GET` Path: `/cats_controller/new`</answer>
-    <answer> HTTP Verb: `NEW` Path: `/cats_controller/`</answer>
-    <explanation>If you are requesting a new form, you'd be making `GET` request. Since this request would lead to a new cat being made, Rails convention dictates that the path would be `/cats/new`.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>Which of the following is **NOT** true about controllers?</p>
-    <answer>The controller lives for only one request response cycle.</answer>
-    <answer>The controller can `render` or `redirect`, but not both.</answer>
-    <answer correct>The `CatsController` is the only controller that can access the `Cat` model.</answer>
-    <answer>The controller's name is conventionally pluralized.</answer>
-    <explanation>Active Record allows us to access the `Cat` model in multiple controllers.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>Assuming RESTful routes, a `GET` request to `/magazines/:magazine_id/articles` would do which of the following?</p>
-    <answer>Call the `articles` action of the `MagazinesController` with `magazine_id` as a key in the `params` hash.</answer>
-    <answer>Call the `index` action of the `MagazinesController` with `articles` as a key in the `params` hash.</answer>
-    <answer correct>Call the `index` action of the `ArticlesController` with `magazine_id` as a key in the `params` hash.</answer>
-    <answer>Call the `articles` action of the `MagazinesController` with `id` as a key in the `params` hash.</answer>
-    <explanation>Since the last piece of the URL is plural and this is a `GET` request, you can assume you are hitting the `index` action on the matching controller (in this case, `articles`). Then looking at the rest of the URL, you can see the `:magazine_id`, meaning that you are passing a `magazine_id` as a key in the `params` hash as part of this request.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question>
-  <p>Which of the following lines, if added to __config/routes.rb__, would cause the root url (i.e., "/") to run the `BicyclesController`'s `index` method when visited?</p>
-    <answer correct>`root "bicycles#index"`</answer>
-    <answer>`resources :bicycles, root: index`</answer>
-    <answer>`root :bicycles#index`</answer>
-    <answer>`resources root to: #index`</answer>
-    <explanation>Proper Rails syntax is essential! Always feel free to visit the Rails documentation if you are ever unsure of the syntax to implement something.</explanation>
-  </question>
-</quiz>
+Where do the key-value pairs in the `params` hash come from? (Select all that apply.)
+- [ ] Query string
+- [ ] The path of the request
+- [ ] Form data from a `POST`/`PATCH`/`PUT` request
+    
+<details><summary>Answer:</summary>
+
+- Query string
+- The path of the request
+- Form data from a `POST`/`PATCH`/`PUT` request</details>
+<details><summary>Explanation:</summary>
+
+All of the above!</details>
+
+The server returned a blank form for creating a cat. Assuming RESTful Routes, which request was made?
+- [ ] HTTP Verb: `NEW` Path: `/cats/`
+- [ ] HTTP Verb: `GET` Path: `/cats/new`
+- [ ] HTTP Verb: `GET` Path: `/cats_controller/new`
+- [ ]  HTTP Verb: `NEW` Path: `/cats_controller/`
+
+<details><summary>Answer:</summary>
+
+HTTP Verb: `GET` Path: `/cats/new`</details>
+<details><summary>Explanation:</summary>
+
+If you are requesting a new form, you'd be making `GET` request. Since this request would lead to a new cat being made, Rails convention dictates that the path would be `/cats/new`.</details>
+
+Which of the following is **NOT** true about controllers?
+- [ ] The controller lives for only one request response cycle.
+- [ ] The controller can `render` or `redirect`, but not both.
+- [ ] The `CatsController` is the only controller that can access the `Cat` model.
+- [ ] The controller's name is conventionally pluralized.
+
+<details><summary>Answer:</summary>
+
+The `CatsController` is the only controller that can access the `Cat` model.</details>
+<details><summary>Explanation:</summary>
+
+Active Record allows us to access the `Cat` model in multiple controllers.</details>
+
+Assuming RESTful routes, a `GET` request to `/magazines/:magazine_id/articles` would do which of the following?
+- [ ] Call the `articles` action of the `MagazinesController` with `magazine_id` as a key in the `params` hash.
+- [ ] Call the `index` action of the `MagazinesController` with `articles` as a key in the `params` hash.
+- [ ] Call the `index` action of the `ArticlesController` with `magazine_id` as a key in the `params` hash.
+- [ ] Call the `articles` action of the `MagazinesController` with `id` as a key in the `params` hash.
+
+<details><summary>Answer:</summary>
+
+Call the `index` action of the `ArticlesController` with `magazine_id` as a key in the `params` hash.</details>
+<details><summary>Explanation:</summary>
+
+Since the last piece of the URL is plural and this is a `GET` request, you can assume you are hitting the `index` action on the matching controller (in this case, `articles`). Then looking at the rest of the URL, you can see the `:magazine_id`, meaning that you are passing a `magazine_id` as a key in the `params` hash as part of this request.</details>
+
+Which of the following lines, if added to __config/routes.rb__, would cause the root url (i.e., "/") to run the `BicyclesController`'s `index` method when visited?
+- [ ] `root "bicycles#index"`
+- [ ] `resources :bicycles, root: index`
+- [ ] `root :bicycles#index`
+- [ ] `resources root to: #index`
+
+<details><summary>Answer:</summary>
+
+`root "bicycles#index"`</details>
+<details><summary>Explanation:</summary>
+
+Proper Rails syntax is essential! Always feel free to visit the Rails documentation if you are ever unsure of the syntax to implement something.</details>
diff --git a/rails/quizzes/testing.md b/rails/quizzes/testing.md
index 534d3ad..5ca15dd 100644
--- a/rails/quizzes/testing.md
+++ b/rails/quizzes/testing.md
@@ -1,15 +1,17 @@
 # Rails Testing
 
-<quiz>
-  <question>
-  <p>Which of the following should you not test when testing Rails models?</p>
-    <answer>Associations</answer>
-    <answer>Class methods</answer>
-    <answer correct>Private methods</answer>
-    <answer>Validations</answer>
-    <explanation>You should never need to test a `private` method directly. Instead, you would want to test the method that calls the `private` method.</explanation>
-  </question>
-</quiz>
+Which of the following should you not test when testing Rails models?
+- [ ] Associations
+- [ ] Class methods
+- [ ] Private methods
+- [ ] Validations
+
+<details><summary>Answer:</summary>
+
+Private methods</details>
+<details><summary>Explanation:</summary>
+
+You should never need to test a `private` method directly. Instead, you would want to test the method that calls the `private` method.</details>
 
 ```ruby
 # spec/factories/puppies.rb
@@ -21,17 +23,19 @@ FactoryBot.define do
 end
 ```
 
-<quiz>
-  <question>
-  <p>Say you use FactoryBot to build puppies. What, if anything, is wrong with the above puppy factory?</p>
-    <answer>You need to define your factory using the code `FactoryBot.build(:puppy, name: Faker::Name.name))`</answer>
-    <answer>You must say `factory Puppy` instead of `factory :puppy` in order for FactoryBot to know what sort of model you are trying to build.</answer>
-    <answer correct>You need to put `Faker::Name.name` inside a block so that it reads `name { Faker::Name.name }`.</answer>
-    <answer>You should generate a random name using `Faker.name` rather than `Faker::Name.name`.</answer>
-    <answer>Nothing--this factory will produce puppies with random names.</answer>
-    <explanation>FactoryBot will throw an error if you do not wrap `Faker::Name.name`--or any value you want to assign to an attribute--inside a block. (Passing a block enables the values to be generated dynamically.)</explanation>
-  </question>
-</quiz>
+Say you use FactoryBot to build puppies. What, if anything, is wrong with the above puppy factory?
+- [ ] You need to define your factory using the code `FactoryBot.build(:puppy, name: Faker::Name.name))`
+- [ ] You must say `factory Puppy` instead of `factory :puppy` in order for FactoryBot to know what sort of model you are trying to build.
+- [ ] You need to put `Faker::Name.name` inside a block so that it reads `name { Faker::Name.name }`.
+- [ ] You should generate a random name using `Faker.name` rather than `Faker::Name.name`.
+- [ ] Nothing--this factory will produce puppies with random names.
+
+<details><summary>Answer:</summary>
+
+You need to put `Faker::Name.name` inside a block so that it reads `name { Faker::Name.name }`.</details>
+<details><summary>Explanation:</summary>
+
+FactoryBot will throw an error if you do not wrap `Faker::Name.name`--or any value you want to assign to an attribute--inside a block. (Passing a block enables the values to be generated dynamically.)</details>
 
 ```ruby
   describe Puppy do
@@ -51,16 +55,18 @@ end
   end
 ```
 
-<quiz>
-  <question>
-  <p>Assuming that `Puppy::puppies_by_cuteness` is written correctly, why will the above spec fail?</p>
-    <answer correct>`FactoryBot.build` should be changed to `FactoryBot.create` since `Puppy::puppies_by_cuteness` queries the database. </answer>
-    <answer>You cannot use the same factory to build multiple objects.</answer>
-    <answer> You cannot use `FactoryBot` in model tests, only in integration tests.</answer>
-    <answer>The test should read `expect(puppies_by_cuteness).to be([10,9,8])` rather than `expect(puppies_by_cuteness).to eq([10,9,8])`.</answer>
-    <explanation>Calling `FactoryBot.build` is equivalent to calling `Model.new` which will not save to the testing database. If you are querying the database, you need to actually create these Puppies in your database by calling `FactoryBot.create`.</explanation>
-  </question>
-</quiz>
+Assuming that `Puppy::puppies_by_cuteness` is written correctly, why will the above spec fail?
+- [ ] `FactoryBot.build` should be changed to `FactoryBot.create` since `Puppy::puppies_by_cuteness` queries the database. 
+- [ ] You cannot use the same factory to build multiple objects.
+- [ ]  You cannot use `FactoryBot` in model tests, only in integration tests.
+- [ ] The test should read `expect(puppies_by_cuteness).to be([10,9,8])` rather than `expect(puppies_by_cuteness).to eq([10,9,8])`.
+
+<details><summary>Answer:</summary>
+
+`FactoryBot.build` should be changed to `FactoryBot.create` since `Puppy::puppies_by_cuteness` queries the database. </details>
+<details><summary>Explanation:</summary>
+
+Calling `FactoryBot.build` is equivalent to calling `Model.new` which will not save to the testing database. If you are querying the database, you need to actually create these Puppies in your database by calling `FactoryBot.create`.</details>
 
 Consider the following:
 
@@ -79,26 +85,31 @@ feature 'signing up a user' do
 end
 ```
 
-<quiz>
-  <question>
-  <p>The above code represents the syntax for a Capybara feature test. To transform it into typical syntax for a system test, what should you replace `feature`, `background`, and `scenario` with?</p>
-    <answer>`describe`, `before(:all)`, `it`</answer>
-    <answer correct>`describe`, `before`, `it`</answer>
-    <answer>`describe`, `given`, `context`</answer>
-    <answer>`context`, `given`, `describe`</answer>
-    <answer>`describe`, `context`, `it`</answer>
-    <explanation>When converting from Capybara feature DSL, `feature` becomes `describe`, `background` becomes `before`, `scenario` becomes `it`, and `given` becomes `let`.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question multiple>
-  <p>Capybara helps with which of the following kinds of tests? (Select all that apply.) </p>
-    <answer correct>End-to-End tests</answer>
-    <answer correct>Integration tests</answer>
-    <answer>Unit tests</answer>
-    <answer>Manual tests</answer>
-    <answer> None of these answers</answer>
-    <explanation>You use Capybara only for end-to-end tests and integration tests. For unit tests, you can still use regular old `RSpec`.</explanation>
-  </question>
-</quiz>
+The above code represents the syntax for a Capybara feature test. To transform it into typical syntax for a system test, what should you replace `feature`, `background`, and `scenario` with?
+- [ ] `describe`, `before(:all)`, `it`
+- [ ] `describe`, `before`, `it`
+- [ ] `describe`, `given`, `context`
+- [ ] `context`, `given`, `describe`
+- [ ] `describe`, `context`, `it`
+
+<details><summary>Answer:</summary>
+
+`describe`, `before`, `it`</details>
+<details><summary>Explanation:</summary>
+
+When converting from Capybara feature DSL, `feature` becomes `describe`, `background` becomes `before`, `scenario` becomes `it`, and `given` becomes `let`.</details>
+
+Capybara helps with which of the following kinds of tests? (Select all that apply.) 
+- [ ] End-to-End tests
+- [ ] Integration tests
+- [ ] Unit tests
+- [ ] Manual tests
+- [ ]  None of these answers
+
+<details><summary>Answer:</summary>
+
+- End-to-End tests
+- Integration tests</details>
+<details><summary>Explanation:</summary>
+
+You use Capybara only for end-to-end tests and integration tests. For unit tests, you can still use regular old `RSpec`.</details>
diff --git a/rails/quizzes/views.md b/rails/quizzes/views.md
index bb9cffa..4bcf66d 100644
--- a/rails/quizzes/views.md
+++ b/rails/quizzes/views.md
@@ -14,17 +14,19 @@ voter     |  GET     |   /voters/:id(.:format)     |    voters#show
           |  PUT     |   /voters/:id(.:format)     |    voters#update
 ```
 
-<quiz>
-  <question >
-  <p>Suppose you have a form at `/voters/:id/edit` for voters to update their information.  What are the correct `action` and `method` values for that form, respectively?</p>
-    <answer>`/voters/:id`, `post`</answer>
-    <answer>`/voters`, `post`</answer>
-    <answer correct>`/voters/:id`, `patch`</answer>
-    <answer>`/voters/:id/edit`, `patch`</answer>
-    <answer>`/voters`, `patch`</answer>
-    <explanation>The main clue here is that in order for your form to *update* information in the database, it needs to make a `patch` request. If you know the verb is `patch` then you can look in the table above to find the matching URL.</explanation>
-  </question>
-</quiz>
+Suppose you have a form at `/voters/:id/edit` for voters to update their information.  What are the correct `action` and `method` values for that form, respectively?
+- [ ] `/voters/:id`, `post`
+- [ ] `/voters`, `post`
+- [ ] `/voters/:id`, `patch`
+- [ ] `/voters/:id/edit`, `patch`
+- [ ] `/voters`, `patch`
+
+<details><summary>Answer:</summary>
+
+`/voters/:id`, `patch`</details>
+<details><summary>Explanation:</summary>
+
+The main clue here is that in order for your form to *update* information in the database, it needs to make a `patch` request. If you know the verb is `patch` then you can look in the table above to find the matching URL.</details>
 
 ```ruby
 # app/controllers/voters_controller.rb
@@ -47,29 +49,33 @@ end
 </ul>
 ```
 
-<quiz>
-  <question >
-  <p>What is wrong with the above code?</p>
-    <answer>A list item cannot have nested ERB code.</answer>
-    <answer>`VotersController#index` should redirect, not render.</answer>
-    <answer correct>`voters` will be undefined in the index view.</answer>
-    <answer>The index page should show information for only one voter.</answer>
-    <answer>Nothing is wrong.</answer>
-    <explanation>An HTML view can only access a controller's **instance variables**, not its local variables. Accordingly, for the code above to work, the `index` controller would need to store the `Voter`s in an instance variable--e.g., `@voters`--that the HTML view then accesses.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question >
-  <p>Which of the following is **NOT** a valid HTTP verb?</p>
-    <answer>`GET`</answer>
-    <answer>`PATCH`</answer>
-    <answer>`PUT`</answer>
-    <answer correct>`DESTROY`</answer>
-    <answer>`POST`</answer>
-    <explanation>This one is tricky! The HTTP verb is not destroy but `DELETE`.</explanation>
-  </question>
-</quiz>
+What is wrong with the above code?
+- [ ] A list item cannot have nested ERB code.
+- [ ] `VotersController#index` should redirect, not render.
+- [ ] `voters` will be undefined in the index view.
+- [ ] The index page should show information for only one voter.
+- [ ] Nothing is wrong.
+
+<details><summary>Answer:</summary>
+
+`voters` will be undefined in the index view.</details>
+<details><summary>Explanation:</summary>
+
+An HTML view can only access a controller's **instance variables**, not its local variables. Accordingly, for the code above to work, the `index` controller would need to store the `Voter`s in an instance variable--e.g., `@voters`--that the HTML view then accesses.</details>
+
+Which of the following is **NOT** a valid HTTP verb?
+- [ ] `GET`
+- [ ] `PATCH`
+- [ ] `PUT`
+- [ ] `DESTROY`
+- [ ] `POST`
+
+<details><summary>Answer:</summary>
+
+`DESTROY`</details>
+<details><summary>Explanation:</summary>
+
+This one is tricky! The HTTP verb is not destroy but `DELETE`.</details>
 
 ```ruby
 class VotersController < ApplicationController
@@ -95,26 +101,30 @@ class VotersController < ApplicationController
 end
 ```
 
-<quiz>
-  <question >
-  <p>What is wrong with the above code?</p>
-    <answer>The voter params are not properly filtered.</answer>
-    <answer>`update` will not persist to the database.</answer>
-    <answer correct>It may throw a double render error.</answer>
-    <answer>`update` should not render the `edit` template.</answer>
-    <explanation>A Rails controller cannot `render` twice. (`redirect_to` counts as a form of `render`.) In the code above, a successful `update` would cause the controller to attempt both to `redirect` and, because there is no `return` statement after the `redirect`, to `render`.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question >
-  <p>In the Gemfile for a Rails project, in which block should the `binding_of_caller` and `better_errors` gems be nested?</p>
-    <answer correct>`group :development`</answer>
-    <answer>`group :production`</answer>
-    <answer>They should not be nested within any block</answer>
-    <explanation>Since `binding_of_caller` and `better_errors` create a security risk by exposing the inner workings of your code, you never want to include them in a `production` environment. They can also lead to false results in a `test` environment. Accordingly, you should nest them in the `development` group.</explanation>
-  </question>
-</quiz>
+What is wrong with the above code?
+- [ ] The voter params are not properly filtered.
+- [ ] `update` will not persist to the database.
+- [ ] It may throw a double render error.
+- [ ] `update` should not render the `edit` template.
+
+ <details><summary>Answer:</summary>
+
+It may throw a double render error.</details>
+<details><summary>Explanation:</summary>
+
+A Rails controller cannot `render` twice. (`redirect_to` counts as a form of `render`.) In the code above, a successful `update` would cause the controller to attempt both to `redirect` and, because there is no `return` statement after the `redirect`, to `render`.</details>
+
+In the Gemfile for a Rails project, in which block should the `binding_of_caller` and `better_errors` gems be nested?
+- [ ] `group :development`
+- [ ] `group :production`
+- [ ] They should not be nested within any block
+
+<details><summary>Answer:</summary>
+
+`group :development`</details>
+<details><summary>Explanation:</summary>
+
+Since `binding_of_caller` and `better_errors` create a security risk by exposing the inner workings of your code, you never want to include them in a `production` environment. They can also lead to false results in a `test` environment. Accordingly, you should nest them in the `development` group.</details>
 
 ```html
 <!--  _form.html.erb -->
@@ -136,15 +146,17 @@ end
   <%= render 'form', voter: @voter %>
 ```
 
-<quiz>
-  <question >
-  <p>What is wrong with the above code snippet?</p>
-    <answer>The name of partial is wrong; it should be `_form`.</answer>
-    <answer>Forms cannot span two templates.</answer>
-    <answer>The params are incorrectly nested.</answer>
-    <answer>Form action must use a Rails url helper method.</answer>
-    <answer correct>`@voter.id` needs to be evaluated within printing ERB tags.</answer>
-    <answer>There is nothing wrong.</answer>
-    <explanation>ERB won't interpolate values unless they are within printing ERB tags!</explanation>
-  </question>
-</quiz>
+What is wrong with the above code snippet?
+- [ ] The name of partial is wrong; it should be `_form`.
+- [ ] Forms cannot span two templates.
+- [ ] The params are incorrectly nested.
+- [ ] Form action must use a Rails url helper method.
+- [ ] `@voter.id` needs to be evaluated within printing ERB tags.
+- [ ] There is nothing wrong.
+
+<details><summary>Answer:</summary>
+
+`@voter.id` needs to be evaluated within printing ERB tags.</details>
+<details><summary>Explanation:</summary>
+
+ERB won't interpolate values unless they are within printing ERB tags!</details>
diff --git a/rails/quizzes_originals/auth.md b/rails/quizzes_originals/auth.md
new file mode 100644
index 0000000..b3ff324
--- /dev/null
+++ b/rails/quizzes_originals/auth.md
@@ -0,0 +1,60 @@
+# Rails Auth
+
+<quiz>
+  <question >
+  <p>Which of the following statements about cookies are true? They are ...</p>
+    <answer>Stored on the server.</answer>
+    <answer correct>Uploaded with every HTTP request.</answer>
+    <answer>Safe from attacks.</answer>
+    <explanation>Cookies are stored with the client's browser and are therefore not safe from attack!</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question >
+  <p>T/F: Model instances get destroyed after an HTTP response has been sent by Rails.</p>
+    <answer correct>True</answer>
+    <answer>False</answer>
+    <explanation>True! With the end of each HTTP response all model instances are destroyed.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question multiple>
+  <p>Which of the following statements about `Flash` and `Flash.now` are true? (Select all that apply.)</p>
+    <answer correct>`Flash` is accessible during the next request; `Flash.now` is accessible only during the current request</answer>
+    <answer>`Flash.now` is accessible during the next request; `Flash`is accessible only during the current request</answer>
+    <answer correct>`Flash`is usually used with redirects while `Flash.now` is usually used with renders</answer>
+    <answer>`Flash.now` is usually used with redirects while `Flash`is usually used with renders</answer>
+    <explanation>`Flash` is accessible during the next request which is why you use it with redirects. `Flash.now` is accessible during the current request which is why you use it with `render`.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>What is a CSRF attack?</p>
+    <answer>A Cross-Site Response Fraud attack in which a form fails to submit correctly</answer>
+    <answer correct>A Cross-Site Request Forgery attack in which one site holds a form that acts on another site's server</answer>
+    <answer>A Cross-Site Response Forgery attack in which a form is submitted multiple times from a single click</answer>
+    <explanation>A CSRF attack is when one site holds a form that acts on another site's server. One site would be creating a *request forgery* to another site.</explanation>
+  </question>
+</quiz>
+
+```html
+<input
+  type="hidden"
+  name="authenticity_token"
+  value="<% form_authenticity_token %>"
+/>
+```
+
+<quiz>
+  <question>
+  <p>What is wrong with the above code?</p>
+    <answer>The input type should be `text` instead of `hidden`.</answer>
+    <answer>The name should be `form_authenticity_token` and the value should be `authenticity_token`.</answer>
+    <answer correct>It uses incorrect ERB tags for the value attribute.</answer>
+    <answer>The input needs a label surrounding it.</answer>
+    <explanation>If you want the value to be returned, you need to use printing ERB tags (`<%= %>`)</explanation>
+  </question>
+</quiz>
diff --git a/rails/quizzes_originals/css.md b/rails/quizzes_originals/css.md
new file mode 100644
index 0000000..3de0b64
--- /dev/null
+++ b/rails/quizzes_originals/css.md
@@ -0,0 +1,159 @@
+# CSS
+
+<quiz>
+  <question>
+  <p>Which of the following does **NOT** belong in the HTML `head` section?</p>
+    <answer>`meta` tags</answer>
+    <answer>`script` tags</answer>
+    <answer correct>a `navbar`</answer>
+    <answer>`link` tags to load in CSS</answer>
+    <explanation>A `navbar` belongs within the `body` tag.</explanation>
+  </question>
+</quiz>
+
+```html
+<!-- Think back on the rules for selector precedence and consider the following: -->
+<style>
+  p {
+    color: red;
+  }
+  p span {
+    color: yellow;
+  }
+  p.small {
+    font-size: 12px;
+  }
+  #big {
+    font-size: 80px;
+  }
+</style>
+
+<p class="small" id="big">
+  <span>Some Text</span>
+</p>
+```
+
+<quiz>
+  <question>
+  <p>What will be the `font-size` and `color` of the text?</p>
+    <answer correct>`color: yellow`, `font-size: 80px`</answer>
+    <answer>`color: red`, `font-size: 80px`</answer>
+    <answer>`color: yellow`, `font-size: 12px`</answer>
+    <answer>`color: red`, `font-size: 12px`</answer>
+    <explanation>The `id` attribute takes precedence over the other attributes, so the `#big` CSS rule would ensure the `font-size: 80px`. Then the specificity of the `span` tag inheriting from the `p` tag would ensure the `color` would be `yellow`.</explanation>
+  </question>
+</quiz>
+
+```html
+<!-- Think back on the rules for selector precedence and consider the following: -->
+<style>
+  * {
+    color: blue;
+  }
+  section p {
+    color: red;
+  }
+  article p {
+    color: yellow;
+  }
+</style>
+
+<article>
+  <section>
+    <p>
+      It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness...
+    </p>
+  </section>
+</article>
+```
+
+<quiz>
+  <question>
+  <p>What will be the `color` of the text?</p>
+    <answer>red</answer>
+    <answer correct>yellow</answer>
+    <answer>blue</answer>
+    <explanation>Precedence wins again! Since both the `section` and the `p` tag inherit from the `article` tag then the color of the text will be `yellow`. </explanation>
+  </question>
+</quiz>
+
+```html
+<!-- Consider the following: -->
+<style>
+  body {
+    background-color: white;
+  }
+
+  p {
+    background-color: wheat;
+    margin: ?;
+    padding: ?;
+  }
+</style>
+
+<p>First Paragraph</p>
+<p>Second Paragraph</p>
+<p>Third Paragraph</p>
+```
+
+<quiz>
+  <question>
+  <p>Let's make the paragraphs display with 10 pixels of white space between them. What should the above `margin` and `padding` properties be set to?</p>
+    <answer>`margin: 5px`, `padding: 0`</answer>
+    <answer>`margin: 5px`, `padding: 5px`</answer>
+    <answer>`margin: 5px`, `padding: 10px`</answer>
+    <answer correct>`margin: 10px`, `padding: 0`</answer>
+    <answer>`margin: 0px`, `padding: 10px`</answer>
+    <explanation>For this problem you just need margin! Try experimenting with the different answers to see why.</explanation>
+  </question>
+</quiz>
+
+```html
+<!-- Consider the following: -->
+
+<style>
+  section {
+    height: 100px;
+    width: 100px;
+  }
+</style>
+
+<section>I AM A SECTION</section>
+<section>I AM ALSO A SECTION</section>
+```
+
+<quiz>
+  <question multiple>
+  <p>You want the `section`s to appear next to each other, and for each `section` to be `100px` tall and `100px` wide. Which of the following properties could you add to the `section` styling to achieve this? (Select all that apply.)</p>
+    <answer>`display: inline`</answer>
+    <answer correct>`display: inline-block`</answer>
+    <answer correct>`float: left`</answer>
+    <answer>None of these answers</answer>
+    <explanation>Both `display: inline-block` and `float: left` could achieve the look you are after!</explanation>
+  </question>
+</quiz>
+
+```html
+<!-- Consider the following: -->
+<style>
+  p {
+    color: red;
+    font-size: 16px;
+  }
+</style>
+
+<p style="color: #FFFFFF; font-size: 12px">
+  Some Text
+</p>
+```
+
+<quiz>
+  <question>
+  <p>What will be the `p` tag's color and font size?</p>
+    <answer>`red`, `16px`</answer>
+    <answer>`red`, `12px`</answer>
+    <answer correct>`#FFFFFF`, `12px` </answer>
+    <answer>`#FFFFFF`, `16px`</answer>
+    <explanation>Inline styling will always be the most specific and will override any other CSS rule.</explanation>
+  </question>
+</quiz>
diff --git a/rails/quizzes_originals/rails_forms.md b/rails/quizzes_originals/rails_forms.md
new file mode 100644
index 0000000..3a23c87
--- /dev/null
+++ b/rails/quizzes_originals/rails_forms.md
@@ -0,0 +1,87 @@
+# Rails Forms
+
+```html
+<input type='hidden' name='cat[tag_ids][]' value=''>
+```
+
+<quiz>
+  <question>
+  <p>What is the purpose of the above line of code?</p>
+    <answer>To set the 'tag_ids' to all available tags, the default value.</answer>
+    <answer>To prevent any 'tag_ids' from being displayed on the page.</answer>
+    <answer correct>To ensure 'tag_ids' is set to an empty array even if nothing was selected.</answer>
+    <explanation>To ensure that 'tag_ids' sends an empty array even if no selection was made, you can set the `name` to `cat[tag_ids][]`. </explanation>
+  </question>
+</quiz>
+
+```ruby
+# Consider the following code:
+
+# cats_controller.rb
+def index
+  if params[:tag]
+    @cats = Tag.find_by(name: params[:tag]).cats
+  else
+    @cats = Cat.all
+  end
+
+  render :index
+end
+```
+
+<quiz>
+  <question>
+  <p>What will a GET request to `/cats?cat_name=Markov` result in?</p>
+    <answer correct>A list of all the cats.</answer>
+    <answer>Only the cats named 'Markov'.</answer>
+    <answer>An error.</answer>
+    <explanation>Since there is no `tag` parameter being passed in, the above request will produce a list of all the cats.</explanation>
+  </question>
+</quiz>
+
+```ruby
+# Consider the following code:
+
+# cats_controller.rb
+def index
+  if params[:tag]
+    @cats = Tag.find_by(name: params[:tag]).cats
+  else
+    @cats = Cat.all
+  end
+
+  render :index
+end
+```
+
+<quiz>
+  <question>
+  <p>What will a GET request to `/cats?tag=athletic` result in?</p>
+    <answer>A list of all the cats.</answer>
+    <answer correct>A list of all the cats tagged 'athletic'.</answer>
+    <answer> An empty list, no cats.</answer>
+    <answer> An error.</answer>
+    <explanation>This request has a `tag` parameter, so it will produce a list of all the cats tagged 'athletic'.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question multiple>
+  <p>How are concerns different from regular modules? (Select all that apply.)</p>
+    <answer correct>They can run code in the class scope at the time they are included.</answer>
+    <answer correct>They have their own dedicated folders in the default Rails folder hierarchy.</answer>
+    <answer correct>They include the line 'extend ActiveSupport::Concern'</answer>
+    <explanation>All of the above!</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>What extra key-value pair must be added to a 'belongs_to' association to enable polymorphic associative behavior?</p>
+    <answer correct>`polymorphic: true`</answer>
+    <answer>`polymorphic_key: :id`</answer>
+    <answer>`as: :polymorphic`</answer>
+    <answer>`as: :pictureable`</answer>
+    <explanation>It's as simple as marking the association `polymorphic: true`.</explanation>
+  </question>
+</quiz>
diff --git a/rails/quizzes_originals/rails_lite.md b/rails/quizzes_originals/rails_lite.md
new file mode 100644
index 0000000..ee10d60
--- /dev/null
+++ b/rails/quizzes_originals/rails_lite.md
@@ -0,0 +1,73 @@
+# Rails Lite
+
+<quiz>
+  <question>
+  <p>Which of the following is **NOT** part of an HTTP request?</p>
+    <answer>HTTP method</answer>
+    <answer correct>Status Code</answer>
+    <answer>Request Header</answer>
+    <answer>Request Target</answer>
+    <answer>HTTP Protocol Version</answer>
+    <explanation>The status code is the only thing not included in an HTTP request.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>Which list contains only items that the Rails framework provides for you when creating a default Rails project?</p>
+    <answer>jQuery, RSpec, The Router  </answer>
+    <answer>The Database, WEBrick, Sinatra</answer>
+    <answer>Routes, Models, Controllers, Views</answer>
+    <answer correct>Rack, Active Record Base, Action Controller, Puma</answer>
+    <answer>Active Record Base, Models, The Router, HTTP</answer>
+    <explanation>Rails only provides the Rack, Active Record Base, Action Controller, and Puma.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>Suppose you want to capture only the part of the URL that comes **before** the query string. Using Regex, what is the best way to do this?</p>
+    <answer>`/^(\?)/`</answer>
+    <answer>`/\\?\w+\=/`</answer>
+    <answer correct>`/^[^\?]*/`</answer>
+    <answer>`/\.\w+\/\w+\\?/`</answer>
+    <answer>`/http:\/\/\w+\.\w+\//`</answer>
+    <explanation>You want to match everything before the `?` in the URL. The first `^` says to start at the beginning of the string. `[^\?]` says to match any single character that is not (`^`) `?`. Finally, the `*` says to match this single-character-that-is-not-? between 0 and an unlimited number of times.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>Imagine you make a request to the Google Maps API but accidentally enter an incorrect API key. What response status would you expect to get back?</p>
+    <answer>204</answer>
+    <answer>301</answer>
+    <answer correct>401</answer>
+    <answer>404</answer>
+    <answer>418</answer>
+    <explanation>The 401 (Unauthorized) status code indicates that the request has not been applied because it lacks valid authentication credentials for the target resource.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>What does `Rack::Response#write` do? It ...</p>
+    <answer>Creates a mock GET request object from the given string.</answer>
+    <answer>Parses the given text string into an HTML request.</answer>
+    <answer>Sets the body of the request to the given string.</answer>
+    <answer>Formats stored response data into properly formatted HTTP.</answer>
+    <answer correct>Appends the given string to the body and updates Content-Length.</answer>
+    <explanation>`Rack::Response#write` appends the given string to the body and updates Content-Length.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>Which of the following is **NOT** an example of middleware?</p>
+    <answer>A static asset server</answer>
+    <answer>Request authentication</answer>
+    <answer>A server log</answer>
+    <answer>A browser filter that redirects you to download Chrome if you visit the site using IE</answer>
+    <answer correct>The main web application</answer>
+    <explanation>Middleware can do many different things, but middleware's purpose is to allow software developers to focus on the specific purpose of their application. So the main web application is **not** an example of middleware.</explanation>
+  </question>
+</quiz>
diff --git a/rails/quizzes_originals/routes_and_controllers.md b/rails/quizzes_originals/routes_and_controllers.md
new file mode 100644
index 0000000..1b3f0a6
--- /dev/null
+++ b/rails/quizzes_originals/routes_and_controllers.md
@@ -0,0 +1,55 @@
+# Routes and Controllers
+
+<quiz>
+  <question multiple>
+  <p>Where do the key-value pairs in the `params` hash come from? (Select all that apply.)</p>
+    <answer correct>Query string</answer>
+    <answer correct>The path of the request</answer>
+    <answer correct>Form data from a `POST`/`PATCH`/`PUT` request</answer>
+    <explanation>All of the above!</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>The server returned a blank form for creating a cat. Assuming RESTful Routes, which request was made?</p>
+    <answer>HTTP Verb: `NEW` Path: `/cats/`</answer>
+    <answer correct> HTTP Verb: `GET` Path: `/cats/new`</answer>
+    <answer>HTTP Verb: `GET` Path: `/cats_controller/new`</answer>
+    <answer> HTTP Verb: `NEW` Path: `/cats_controller/`</answer>
+    <explanation>If you are requesting a new form, you'd be making `GET` request. Since this request would lead to a new cat being made, Rails convention dictates that the path would be `/cats/new`.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>Which of the following is **NOT** true about controllers?</p>
+    <answer>The controller lives for only one request response cycle.</answer>
+    <answer>The controller can `render` or `redirect`, but not both.</answer>
+    <answer correct>The `CatsController` is the only controller that can access the `Cat` model.</answer>
+    <answer>The controller's name is conventionally pluralized.</answer>
+    <explanation>Active Record allows us to access the `Cat` model in multiple controllers.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>Assuming RESTful routes, a `GET` request to `/magazines/:magazine_id/articles` would do which of the following?</p>
+    <answer>Call the `articles` action of the `MagazinesController` with `magazine_id` as a key in the `params` hash.</answer>
+    <answer>Call the `index` action of the `MagazinesController` with `articles` as a key in the `params` hash.</answer>
+    <answer correct>Call the `index` action of the `ArticlesController` with `magazine_id` as a key in the `params` hash.</answer>
+    <answer>Call the `articles` action of the `MagazinesController` with `id` as a key in the `params` hash.</answer>
+    <explanation>Since the last piece of the URL is plural and this is a `GET` request, you can assume you are hitting the `index` action on the matching controller (in this case, `articles`). Then looking at the rest of the URL, you can see the `:magazine_id`, meaning that you are passing a `magazine_id` as a key in the `params` hash as part of this request.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question>
+  <p>Which of the following lines, if added to __config/routes.rb__, would cause the root url (i.e., "/") to run the `BicyclesController`'s `index` method when visited?</p>
+    <answer correct>`root "bicycles#index"`</answer>
+    <answer>`resources :bicycles, root: index`</answer>
+    <answer>`root :bicycles#index`</answer>
+    <answer>`resources root to: #index`</answer>
+    <explanation>Proper Rails syntax is essential! Always feel free to visit the Rails documentation if you are ever unsure of the syntax to implement something.</explanation>
+  </question>
+</quiz>
diff --git a/rails/quizzes_originals/testing.md b/rails/quizzes_originals/testing.md
new file mode 100644
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--- /dev/null
+++ b/rails/quizzes_originals/testing.md
@@ -0,0 +1,104 @@
+# Rails Testing
+
+<quiz>
+  <question>
+  <p>Which of the following should you not test when testing Rails models?</p>
+    <answer>Associations</answer>
+    <answer>Class methods</answer>
+    <answer correct>Private methods</answer>
+    <answer>Validations</answer>
+    <explanation>You should never need to test a `private` method directly. Instead, you would want to test the method that calls the `private` method.</explanation>
+  </question>
+</quiz>
+
+```ruby
+# spec/factories/puppies.rb
+
+FactoryBot.define do
+  factory :puppy do
+    name Faker::Name.name
+  end
+end
+```
+
+<quiz>
+  <question>
+  <p>Say you use FactoryBot to build puppies. What, if anything, is wrong with the above puppy factory?</p>
+    <answer>You need to define your factory using the code `FactoryBot.build(:puppy, name: Faker::Name.name))`</answer>
+    <answer>You must say `factory Puppy` instead of `factory :puppy` in order for FactoryBot to know what sort of model you are trying to build.</answer>
+    <answer correct>You need to put `Faker::Name.name` inside a block so that it reads `name { Faker::Name.name }`.</answer>
+    <answer>You should generate a random name using `Faker.name` rather than `Faker::Name.name`.</answer>
+    <answer>Nothing--this factory will produce puppies with random names.</answer>
+    <explanation>FactoryBot will throw an error if you do not wrap `Faker::Name.name`--or any value you want to assign to an attribute--inside a block. (Passing a block enables the values to be generated dynamically.)</explanation>
+  </question>
+</quiz>
+
+```ruby
+  describe Puppy do
+    describe '::puppies_by_cuteness' do
+      it 'should rank puppies in order of cuteness' do
+        cute_puppy = FactoryBot.build(:puppy, cuteness: 8)
+        cuter_puppy = FactoryBot.build(:puppy, cuteness: 9)
+        cutest_puppy = FactoryBot.build(:puppy, cuteness: 10)
+
+        puppies_by_cuteness = Puppy::puppies_by_cuteness.map do |puppy|
+          puppy.cuteness
+        end
+
+        expect(puppies_by_cuteness).to eq([10,9,8])
+      end
+    end
+  end
+```
+
+<quiz>
+  <question>
+  <p>Assuming that `Puppy::puppies_by_cuteness` is written correctly, why will the above spec fail?</p>
+    <answer correct>`FactoryBot.build` should be changed to `FactoryBot.create` since `Puppy::puppies_by_cuteness` queries the database. </answer>
+    <answer>You cannot use the same factory to build multiple objects.</answer>
+    <answer> You cannot use `FactoryBot` in model tests, only in integration tests.</answer>
+    <answer>The test should read `expect(puppies_by_cuteness).to be([10,9,8])` rather than `expect(puppies_by_cuteness).to eq([10,9,8])`.</answer>
+    <explanation>Calling `FactoryBot.build` is equivalent to calling `Model.new` which will not save to the testing database. If you are querying the database, you need to actually create these Puppies in your database by calling `FactoryBot.create`.</explanation>
+  </question>
+</quiz>
+
+Consider the following:
+
+```ruby
+feature 'signing up a user' do
+  background do
+    visit new_user_url
+    fill_in 'username', with: 'testing_username'
+    fill_in 'password', with: 'biscuits'
+    click_on 'Create User'
+  end
+
+  scenario 'redirects to team index page after signup' do
+    expect(page).to have_content 'Team Index Page'
+  end
+end
+```
+
+<quiz>
+  <question>
+  <p>The above code represents the syntax for a Capybara feature test. To transform it into typical syntax for a system test, what should you replace `feature`, `background`, and `scenario` with?</p>
+    <answer>`describe`, `before(:all)`, `it`</answer>
+    <answer correct>`describe`, `before`, `it`</answer>
+    <answer>`describe`, `given`, `context`</answer>
+    <answer>`context`, `given`, `describe`</answer>
+    <answer>`describe`, `context`, `it`</answer>
+    <explanation>When converting from Capybara feature DSL, `feature` becomes `describe`, `background` becomes `before`, `scenario` becomes `it`, and `given` becomes `let`.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question multiple>
+  <p>Capybara helps with which of the following kinds of tests? (Select all that apply.) </p>
+    <answer correct>End-to-End tests</answer>
+    <answer correct>Integration tests</answer>
+    <answer>Unit tests</answer>
+    <answer>Manual tests</answer>
+    <answer> None of these answers</answer>
+    <explanation>You use Capybara only for end-to-end tests and integration tests. For unit tests, you can still use regular old `RSpec`.</explanation>
+  </question>
+</quiz>
diff --git a/rails/quizzes_originals/views.md b/rails/quizzes_originals/views.md
new file mode 100644
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+++ b/rails/quizzes_originals/views.md
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+# Rails Views
+
+```ruby
+# Consider the following routes table:
+
+Prefix    |   Verb   |     URI Pattern             |  Controller#Action
+---------------------------------------------------------------
+voters    |  GET     |   /voters(.:format)         |    voters#index
+          |  POST    |   /voters(.:format)         |    voters#create
+new_voter |  GET     |   /voters/new               |    voters#new
+edit_voter|  GET     |   /voters/:id/edit(.:format)|    voters#edit
+voter     |  GET     |   /voters/:id(.:format)     |    voters#show
+          |  PATCH   |   /voters/:id(.:format)     |    voters#update
+          |  PUT     |   /voters/:id(.:format)     |    voters#update
+```
+
+<quiz>
+  <question >
+  <p>Suppose you have a form at `/voters/:id/edit` for voters to update their information.  What are the correct `action` and `method` values for that form, respectively?</p>
+    <answer>`/voters/:id`, `post`</answer>
+    <answer>`/voters`, `post`</answer>
+    <answer correct>`/voters/:id`, `patch`</answer>
+    <answer>`/voters/:id/edit`, `patch`</answer>
+    <answer>`/voters`, `patch`</answer>
+    <explanation>The main clue here is that in order for your form to *update* information in the database, it needs to make a `patch` request. If you know the verb is `patch` then you can look in the table above to find the matching URL.</explanation>
+  </question>
+</quiz>
+
+```ruby
+# app/controllers/voters_controller.rb
+class VotersController < ApplicationController
+  def index
+    voters = Voter.all
+    render :index
+  end
+end
+```
+
+```html
+<!-- app/views/voters/index.html.erb -->
+<h1>List of Registered Voters:</h1>
+
+<ul>
+  <% voters.each do |voter| %>
+    <li> <%= voter.full_name %> </li>
+  <% end %>
+</ul>
+```
+
+<quiz>
+  <question >
+  <p>What is wrong with the above code?</p>
+    <answer>A list item cannot have nested ERB code.</answer>
+    <answer>`VotersController#index` should redirect, not render.</answer>
+    <answer correct>`voters` will be undefined in the index view.</answer>
+    <answer>The index page should show information for only one voter.</answer>
+    <answer>Nothing is wrong.</answer>
+    <explanation>An HTML view can only access a controller's **instance variables**, not its local variables. Accordingly, for the code above to work, the `index` controller would need to store the `Voter`s in an instance variable--e.g., `@voters`--that the HTML view then accesses.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question >
+  <p>Which of the following is **NOT** a valid HTTP verb?</p>
+    <answer>`GET`</answer>
+    <answer>`PATCH`</answer>
+    <answer>`PUT`</answer>
+    <answer correct>`DESTROY`</answer>
+    <answer>`POST`</answer>
+    <explanation>This one is tricky! The HTTP verb is not destroy but `DELETE`.</explanation>
+  </question>
+</quiz>
+
+```ruby
+class VotersController < ApplicationController
+  def edit
+    @voter = Voter.find_by(id: params[:id])
+    render :edit
+  end
+
+  def update
+    @voter = Voter.find_by(id: params[:id])
+
+    if @voter.update(voter_params)
+      redirect_to voter_url(@voter)
+    end
+
+    render :edit
+  end
+
+  private
+  def voter_params
+    params.require(:voter).permit(:name, :ssn)
+  end
+end
+```
+
+<quiz>
+  <question >
+  <p>What is wrong with the above code?</p>
+    <answer>The voter params are not properly filtered.</answer>
+    <answer>`update` will not persist to the database.</answer>
+    <answer correct>It may throw a double render error.</answer>
+    <answer>`update` should not render the `edit` template.</answer>
+    <explanation>A Rails controller cannot `render` twice. (`redirect_to` counts as a form of `render`.) In the code above, a successful `update` would cause the controller to attempt both to `redirect` and, because there is no `return` statement after the `redirect`, to `render`.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question >
+  <p>In the Gemfile for a Rails project, in which block should the `binding_of_caller` and `better_errors` gems be nested?</p>
+    <answer correct>`group :development`</answer>
+    <answer>`group :production`</answer>
+    <answer>They should not be nested within any block</answer>
+    <explanation>Since `binding_of_caller` and `better_errors` create a security risk by exposing the inner workings of your code, you never want to include them in a `production` environment. They can also lead to false results in a `test` environment. Accordingly, you should nest them in the `development` group.</explanation>
+  </question>
+</quiz>
+
+```html
+<!--  _form.html.erb -->
+  <label for="name"></label>
+  <input type="text" name="voter[name]" id="name">
+
+  <label for="ssn"></label>
+  <input type="text" name="voter[ssn]" id="ssn">
+
+  <input type="submit" value="Submit!">
+</form>
+
+<!--  edit.html.erb -->
+<h1>Update Voter!</h1>
+
+<form action="/voters/#{@voter.id}" method="post">
+  <input type="hidden" name="_method" value="patch">
+
+  <%= render 'form', voter: @voter %>
+```
+
+<quiz>
+  <question >
+  <p>What is wrong with the above code snippet?</p>
+    <answer>The name of partial is wrong; it should be `_form`.</answer>
+    <answer>Forms cannot span two templates.</answer>
+    <answer>The params are incorrectly nested.</answer>
+    <answer>Form action must use a Rails url helper method.</answer>
+    <answer correct>`@voter.id` needs to be evaluated within printing ERB tags.</answer>
+    <answer>There is nothing wrong.</answer>
+    <explanation>ERB won't interpolate values unless they are within printing ERB tags!</explanation>
+  </question>
+</quiz>
diff --git a/rails/rails_diagram.png b/rails/rails_diagram.png
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+Subproject commit 4fa36f89e5605a7a0418c345d1817db5ddba2829
diff --git a/ruby/Open_Ruby_Overview.md b/ruby/Open_Ruby_Overview.md
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+++ b/ruby/Open_Ruby_Overview.md
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+# Ruby
+
+## Topics Covered
+
+- [Enumerables and Debugging](#enumerables-and-debugging)
+- [References](#reference)
+- [Recursion](#recursion)
+- [Git](#git)
+- [Data Structures](#data-structures)
+- [Object-Oriented Programming](#object-oriented-programming)
+- [RSpec and TDD](#rspec-and-tdd)
+- [Big-O](#big-o)
+- [LRU Cache](#lru-cache)
+
+## Notes
+
+Ruby is the first module in the App Academy Full Stack Developer Curriculum. All
+of the material that you cover in these modules will seek to build upon previous
+days and as such, going back to review previous readings or videos will be in
+your best interest when time allows.
+
+As with all future modules, any "Bonus" projects are to be completed after the
+standard projects for each day are completed. Sometimes that could mean going
+back to previous day's "Bonus" projects if you otherwise finish early.
+Additional Resources are readings, videos, or articles that are not required,
+but will serve to deepen your understanding of a topic. They will be denoted
+with a specific icon in your task menu.
+
+## Lessons
+### Getting Started
+- [ ] 1. [Setting up a Development Environment (Phase 1)](../course/readings/dev-setup.md)
+### Enumerables and Debugging
+- [ ] 1. [Nontechnical Overview of Ruby](readings/ruby_nontech.md)
+- [ ] 2. [Debugging](readings/debugger.md)
+- [ ] 3. [Common Exceptions](readings/common-exceptions.md)
+- [ ] 4. [More Byebug Commands: display and where](readings/bonus-debugger.md)
+- [ ] 5. [Debugging Cheatsheet](readings/debugging_cheatsheet.md)
+- [ ] 6. [Breaking Methods Into Parts](readings/breaking-into-parts.md)
+- [ ] 7. [Enumerables](projects/enumerables/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/enumerables/solution.zip)
+- [ ] 8. [Ghost](projects/ghost/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/ghost/solution.zip)
+- [ ] 9. [Maze Solver (Bonus)](projects/maze_solver/README.md)
+  - [Soution](https://assets.aaonline.io/fullstack/ruby/projects/maze_solver/solution.zip)
+- [ ] 10. [Eight Queens Puzzle (Bonus)](https://en.wikipedia.org/wiki/Eight_queens_puzzle)
+- [ ] 11. [Project Euler (Bonus)](https://projecteuler.net/problems)
+### Reference
+- [ ] 1. [References Video](https://player.vimeo.com/video/165965713)
+- [ ] 2. [References](readings/references.md)
+- [ ] 3. [Array/Hash Defaults](readings/array-hash-defaults.md)
+- [ ] 4. [Scope](readings/scope.md)
+- [ ] 5. [DRY (Dont Repeat Yourself)](readings/dry.md)
+- [ ] 6. [Method Decomposition & Design](readings/method-decomposition.md)
+- [ ] 7. [Refactoring and Code Smells](readings/refactoring.md)
+- [ ] 8. [Reference Quiz](quizzes/reference.md)
+- [ ] 9. [VSCode Cheatsheet](../course/readings/vscode_cheatsheet.md)
+- [ ] 10. [Testing Small (from Memory Puzzle)](readings/testing-small.md)
+- [ ] 11. [my_flatten Solution Video](https://player.vimeo.com/video/336469470)
+- [ ] 12. [my_zip Solution Video](https://player.vimeo.com/video/336469834)
+- [ ] 13. [my_rotate Solution Video](https://player.vimeo.com/video/336470349)
+- [ ] 14. [Pass by Reference Lecture](https://player.vimeo.com/video/336470662)
+- [ ] 15. [Hash Defaults Lecture](https://player.vimeo.com/video/336471687)
+- [ ] 16. [Block and Procs Lecture](https://player.vimeo.com/video/336472385)
+- [ ] 17. [Methods Lecture](https://player.vimeo.com/video/336472772)
+- [ ] 18. [Memory Puzzle](projects/memory/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/memory/solution.zip)
+- [ ] 19. [Sudoku](projects/sudoku/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/sudoku/solution.zip)
+- [ ] 20. [Hash and Equals](readings/hash-and-equals.md)
+- [ ] 21. [Swap](readings/swap.md)
+
+### Recursion
+- [ ] 1. [Recursion Intro](https://player.vimeo.com/video/162569408)
+- [ ] 2. [Recursion vs Iteration](https://player.vimeo.com/video/162569439)
+- [ ] 3. [Upcase and Reverse Demo](https://player.vimeo.com/video/162569447)
+- [ ] 4. [Quicksort Intro](https://player.vimeo.com/video/162569453)
+- [ ] 5. [Quicksort Demo](https://player.vimeo.com/video/162569463)
+- [ ] 6. [Stack Overflow Demo](https://player.vimeo.com/video/162569490)
+- [ ] 7. [The Stack](https://player.vimeo.com/video/162571286)
+- [ ] 8. [Recursion](readings/recursion.md)
+- [ ] 9. [Recursion Quiz](quizzes/recursion.md)
+- [ ] 10. [InDepth QuickSort Demo](https://player.vimeo.com/video/337154374)
+- [ ] 11. [Recursion Homework](homeworks/recursion/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/homeworks/recursion/solution.rb)
+- [ ] 12. [Memory Puzzle Solution](https://player.vimeo.com/video/337147003)
+- [ ] 13. [Recursion Intro Lecture](https://player.vimeo.com/video/337152898)
+- [ ] 14. [Recursion exercises](projects/recursion/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/recursion/solution.zip)
+- [ ] 15. [Word Chains](projects/word_chains/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/word_chains/solution.zip)
+- [ ] 16. [More Recursion Questions (Bonus)](projects/more_recursion_exercises/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/more_recursion_exercises/solutions/recursion_problems.rb)
+
+### Git
+- [ ] 1. [Git: Overview and Why We Use Git](https://player.vimeo.com/video/171666454)
+- [ ] 2. [Git: Mental Models](https://player.vimeo.com/video/171666455)
+- [ ] 3. [Git: Useful Commands](https://player.vimeo.com/video/171666453)
+- [ ] 4. [Git: Wrapup](https://player.vimeo.com/video/171666456)
+- [ ] 5. [Why Git](readings/why-git.md)
+- [ ] 6. [Git Summary](readings/git-summary.md)
+- [ ] 7. [Git Workflow](readings/git-workflow.md)
+- [ ] 8. [Gems and rbenv](readings/gems-and-rbenv.md)
+- [ ] 9. [Nontechnical Overview of Git](readings/git_nontech.md)
+- [ ] 10. [Nontechnical Overview of Agile Development](readings/agile_nontech.md)
+- [ ] 11. [Git Quiz](quizzes/git.md)
+- [ ] 12. [Git Workflow Exercises](homeworks/git-workflow-exercises.md)
+- [ ] 13. [Merge Sort Solution](https://player.vimeo.com/video/337155330)
+- [ ] 14. [bSearch Solution](https://player.vimeo.com/video/337165165)
+- [ ] 15. [Serialization (JSON and YAML)](readings/serialization.md)
+- [ ] 16. [Git add](readings/git-add.md)
+- [ ] 17. [Git Repository Clean Up](readings/git-repository-cleanup.md)
+- [ ] 18. [Faster Git with aliases](readings/alias.md)
+- [ ] 19. [Fixing Git commit authorship](readings/git-fix-authorship.md)
+- [ ] 20. [Git Cheatsheet](http://www.ndpsoftware.com/git-cheatsheet.html)
+- [ ] 21. [Student Github Repo Example](https://github.com/aa-repo-examples)
+- [ ] 22. [Git Lecture](https://player.vimeo.com/video/337165903)
+- [ ] 23. [Screwedoku](projects/screwdoku/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/sudoku/solution.zip)
+- [ ] 24. [Minesweeper](projects/minesweeper/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/minesweeper/solution.zip)
+### Data Structures
+- [ ] 1. [Data Structures](https://player.vimeo.com/video/162763729)
+- [ ] 2. [DFS](https://player.vimeo.com/video/162763740)
+- [ ] 3. [Intro to Algorithms and Data Structures](readings/intro-algorithms-and-data-structures.md)
+- [ ] 4. [Inspecting Complex Elements](readings/overriding_inspect.md)
+- [ ] 5. [Data Structures Quiz](quizzes/data_structures.md)
+- [ ] 6. [Homeworks with Git](homeworks/git-homeworks.md)
+- [ ] 7. [DIY ADTs](homeworks/abstract_data_types/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/homeworks/abstract_data_types/solution.rb)
+- [ ] 8. [ADT - Stack & Queues Lecture](https://player.vimeo.com/video/337176180)
+- [ ] 9. [Binary Trees & DFS Lecture](https://player.vimeo.com/video/337177768)
+- [ ] 10. [Binary Trees & DFS Lecture II](https://player.vimeo.com/video/337181557)
+- [ ] 11. [Intro data structures: PolyTreeNode](projects/poly_tree_node/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/poly_tree_node/solution.zip)
+- [ ] 12. [Graph Intro](readings/graph_nodes_reading.md)
+- [ ] 13. [Graph Traversal](readings/graph_traversal_notes_reading.md)
+- [ ] 14. [Graph Nodes and BFS](homeworks/graphs/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/homeworks/graphs/solution.rb)
+- [ ] 15. [Knights Travails](projects/knights_travails/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/knights_travails/solution.zip)
+- [ ] 16. [Knights Travails (Part Two)](projects/knights_travails/part_two.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/knights_travails/solution.zip)
+- [ ] 17. [Tic-Tac-Toe AI](projects/tic_tac_toe_ai/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/tic_tac_toe_ai/solution.zip)
+### Object-oriented programming
+- [ ] 1. [Inheritance](readings/inheritance.md)
+- [ ] 2. [Exceptions, error handling](readings/errors.md)
+- [ ] 3. [Decomposition into objects](readings/object-decomposition.md)
+- [ ] 4. [Inheritance and DRY](readings/inheritance-design.md)
+- [ ] 5. [Information hiding/encapsulation](readings/hiding.md)
+- [ ] 6. [UML](readings/uml.md)
+- [ ] 7. [Singleton](http://ruby-doc.org/stdlib-1.9.3/libdoc/singleton/rdoc/Singleton.html#module-Singleton-label-Usage)
+- [ ] 8. [OOP Quiz 1](quizzes/oop_1.md)
+- [ ] 9. [Simon](homeworks/simon/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/homeworks/simon/solution.zip)
+- [ ] 10. [Stereotype Threat](https://www.nytimes.com/2012/10/07/opinion/sunday/intelligence-and-the-stereotype-threat.html)
+- [ ] 11. [Unconscious Bias in Tech](https://medium.com/@aldynchwelos/unconscious-bias-in-tech-why-women-leave-their-engineering-careers-f9653185d17b)
+- [ ] 12. [When Algorithms Discriminate](https://www.nytimes.com/2015/07/10/upshot/when-algorithms-discriminate.html)
+- [ ] 13. [Implicit Association Test](https://implicit.harvard.edu/implicit/takeatest.html)
+- [ ] 14. [You're More Biased Than You Think](https://www.fastcompany.com/3036627/youre-more-biased-than-you-think)
+- [ ] 15. [Seven Day Bias Cleanse](http://www.lookdifferent.org/what-can-i-do/bias-cleanse)
+- [ ] 16. [Error Handling Funtime](homeworks/error_handling_funtime/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/homeworks/error_handling_funtime/solution.zip)
+- [ ] 17. [Class inheritance](projects/class_inheritance/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/class_inheritance/solution.zip)
+- [ ] 18. [Chess (Part One)](projects/chess/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/chess/solution.zip)
+- [ ] 19. [Chess (Part Two)](projects/chess/part_two.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/chess/solution.zip)
+- [ ] 20. [Chess (Part Three)](projects/chess/part_three.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/chess/solution.zip)
+- [ ] 21. [OOP Quiz 2](quizzes/oop_2.md)
+- [ ] 22. [Mancala](homeworks/mancala/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/homeworks/mancala/solution.zip)
+- [ ] 23. [Knight's Travails Solution](https://player.vimeo.com/video/337182911)
+- [ ] 24. [TTT Solution](https://player.vimeo.com/video/337184604)
+- [ ] 25. [PolyTreeNode Solution](https://player.vimeo.com/video/337176225)
+- [ ] 26. [Method Encapsulation Lecture](https://player.vimeo.com/video/337191439)
+- [ ] 27. [Inheritance & Modules Lecture](https://player.vimeo.com/video/337194155)
+- [ ] 28. [Error Handling Lecture](https://player.vimeo.com/video/337195111)
+- [ ] 29. [Modules](readings/modules.md)
+- [ ] 30. [load/require/require_relative](readings/require.md)
+- [ ] 31. [public/private/protected](readings/privacy.md)
+### RSpec and TDD
+- [ ] 1. [RSpec Syntax](readings/rspec-syntax.md)
+- [ ] 2. [subject and let](readings/subject-and-let.md)
+- [ ] 3. [Order of RSpec methods](readings/rspec-order.md)
+- [ ] 4. [Test doubles](readings/test-doubles.md)
+- [ ] 5. [Intro to RSpec](https://player.vimeo.com/video/192497364)
+- [ ] 6. [Setup and Basic Syntax](https://player.vimeo.com/video/192665133)
+- [ ] 7. [SErrors, Equality Matchers, Subject/Let, and Doubles](https://player.vimeo.com/video/192662950)
+- [ ] 8. [Rspec: Code Demo](https://player.vimeo.com/video/192666370)
+- [ ] 9. [RSpec and TDD Quiz](quizzes/rspec_tdd.md)
+- [ ] 10. [RSpec](homeworks/rspec/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/homeworks/rspec/solution.zip)
+- [ ] 11. [Introduction to RSpec](readings/intro-rspec.md)
+- [ ] 12. [TDD](readings/intro-tdd.md)
+- [ ] 13. [guard-rspec](readings/guard-rspec.md)
+- [ ] 14. [OO Robot RSpec Example](https://assets.aaonline.io/fullstack/ruby/projects/first_tdd/robot_spec.rb)
+- [ ] 15. [Chess Solutions Walkthroughe](https://player.vimeo.com/video/317152522)
+- [ ] 16. [RSpec Lecture - Part One](https://player.vimeo.com/video/317367140)
+- [ ] 17. [RSpec Lecture - Part Two](https://player.vimeo.com/video/317367563)
+- [ ] 18. [Hack Academy](html-css/micro-projects/css_intro/README.md)
+  - [Solution](https://www.appacademy.io/)
+- [ ] 19. [First TDD Projects](projects/first_tdd/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/first_tdd/solution.zip)
+- [ ] 20. [Poker](projects/poker/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/poker/solution.zip)
+- [ ] 21. [How RSpec works document](readings/how-rspec-works.md)
+
+### Big-O
+- [ ] 1. [Motivations for Big-O](https://player.vimeo.com/video/175565088)
+- [ ] 2. [RAM Model of Computation](https://player.vimeo.com/video/175565090)
+- [ ] 3. [Asymptotic Analysis](https://player.vimeo.com/video/175565086)
+- [ ] 4. [The Worst Case](https://player.vimeo.com/video/175565094)
+- [ ] 5. [Common Classifications](https://player.vimeo.com/video/175568501)
+- [ ] 6. [Set Definition](https://player.vimeo.com/video/175568481)
+- [ ] 7. [Space Complexity](https://player.vimeo.com/video/175565092)
+- [ ] 8. [Big O Quiz](quizzes/big_o.md)
+- [ ] 9. [Sorting Complexity](homeworks/sorting_demo/README.md)
+- [ ] 10. [Octopus Problems](homeworks/big_octopus/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/homeworks/big_octopus/solution.rb)
+- [ ] 11. [Plain English explanation of Big O](http://stackoverflow.com/questions/487258/plain-english-explanation-of-big-o)
+- [ ] 12. [Big O Notation](https://www.interviewcake.com/article/ruby/big-o-notation-time-and-space-complexity)
+- [ ] 13. [Merge Sort](https://www.hackerearth.com/practice/algorithms/sorting/merge-sort/visualize/)
+- [ ] 14. [Bubble Sort](https://www.hackerearth.com/practice/algorithms/sorting/bubble-sort/visualize/)
+- [ ] 15. [Big O Cheatsheet](http://bigocheatsheet.com/)
+- [ ] 16. [Big O Intro & Cat Matcher Lecture](https://player.vimeo.com/video/337176296)
+- [ ] 17. [Binary Search and BigO Lecture](https://player.vimeo.com/video/337181856)
+- [ ] 18. [Merge Sort and BigO Lecture](https://player.vimeo.com/video/337186188)
+- [ ] 19. [Execution Time Differences/Algorithms](projects/execution_time_differences/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/execution_time_differences/solution.zip)
+- [ ] 20. [Anagrams](projects/anagrams/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/anagrams/solution.zip)
+- [ ] 21. [Two sum problem](projects/two_sum/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/two_sum/solution.zip)
+- [ ] 22. [Windowed Max Range](projects/max_windowed_range/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/max_windowed_range/solution.zip)
+- [ ] 23. [Benchmarking (Bonus)](projects/benchmarking/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/demos/sorting_demo/sorting_demo.rb#L58-L67)
+### LRU Cache
+- [ ] 1. [Set and Int Set](https://player.vimeo.com/video/159431377)
+- [ ] 2. [Resizing Int Set Part 1](https://player.vimeo.com/video/159433039)
+- [ ] 3. [Resizing Int Set Part 2](https://player.vimeo.com/video/159437719)
+- [ ] 4. [Hashing](https://player.vimeo.com/video/159435811)
+- [ ] 5. [Hash Set](https://player.vimeo.com/video/159438691)
+- [ ] 6. [Linked Lists and Hashmaps](https://player.vimeo.com/video/159440267)
+- [ ] 7. [Caches](https://player.vimeo.com/video/159441490)
+- [ ] 8. [LRU Cache Video](https://player.vimeo.com/video/159435146)
+- [ ] 9. [How Hashes Work](http://www.gotealeaf.com/blog/how-the-hash-works-in-ruby)
+- [ ] 10. [LRU Cache Reading](https://web.archive.org/web/20150710185255/http://mcicpc.cs.atu.edu/archives/2012/mcpc2012/lru/lru.html)
+- [ ] 11. [Dynamic Array (Wikipedia)](https://en.wikipedia.org/wiki/Dynamic_array)
+- [ ] 12. [XOR Reading](readings/xor.md)
+- [ ] 13. [LRU Cache Quiz](quizzes/lru_cache.md)
+- [ ] 14. [LRU Cache](homeworks/lru_cache/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/homeworks/lru_cache/solution.rb)
+- [ ] 15. [Hash Map & LRU Cache](projects/hash_map_lru_cache/README.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/hash_map_lru_cache/solution.zip)
+- [ ] 16. [Hash Map & LRU Cache (Part Two)](projects/hash_map_lru_cache/part_two.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/hash_map_lru_cache/solution.zip)
+- [ ] 17. [Dynamic Array (Bonus)](projects/hash_map_lru_cache/dynamic_array.md)
+  - [Solution](https://assets.aaonline.io/fullstack/ruby/projects/hash_map_lru_cache/solution.zip)
+- [ ] 18. [Basic cursor input](https://github.com/rglassett/ruby-cursor-game)
\ No newline at end of file
diff --git a/ruby/quizzes/big_o.md b/ruby/quizzes/big_o.md
index 9fd05c5..099a344 100644
--- a/ruby/quizzes/big_o.md
+++ b/ruby/quizzes/big_o.md
@@ -1,44 +1,35 @@
 # Big-O Quiz
+Which of the following represents an ordering of strictly increasing time complexity?
+- [ ] $O(n log n) < O(log n) < O(n) < O(n^2) < O(n!) < O(2^n)$
+- [ ] $O(1)$ < $O(log n)$ < $O(n)$ < $O(n log n)$ < $O(n^2)$ < $O(2^n)$ < $O(n!)$
+- [ ] $O(n^3)$ < $O(n^2)$ < $O(2^n)$ < $O(n log n)$ < $O(n)$ < $O(log n)$ < $O(1)$
+- [ ] $O(n)$ < $O(2n)$ < $O(3n)$ < $O(n + 1)$ < $O(n + 2)$ < $O(n + 3)$
+- [ ] $O(1)$ < $O(log n)$ < $O(n)$ < $O(n^2)$ < $O(n!)$ < $O(2^n)$ < $O(n^n)$
 
-<quiz>
-  <question>
-    <p>Which of the following represents an ordering of strictly increasing time complexity?</p>
-    <answer>`O(n log n)` < `O(log n)` < `O(n)` < `O(n^2)` < `O(n!)` < `O(2^n)`</answer>
-    <answer correct>`O(1)` < `O(log n)` < `O(n)` < `O(n log n)` < `O(n^2)` < `O(2^n)` < `O(n!)`</answer>
-    <answer>`O(n^3)` < `O(n^2)` < `O(2^n)` < `O(n log n)` < `O(n)` < `O(log n)` < `O(1)`</answer>
-    <answer>`O(n)` < `O(2n)` < `O(3n)` < `O(n + 1)` < `O(n + 2)` < `O(n + 3)`</answer>
-    <answer>`O(1)` < `O(log n)` < `O(n)` < `O(n^2)` < `O(n!)` < `O(2^n)` < `O(n^n)`</answer>
-    <explanation>Remember `O(1)`, or constant time, is the slowest growing in terms of time complexity and  `O(n!)`, or factorial time, is the fastest growing.</explanation>
-  </question>
-</quiz>
+<details><summary>Answer:</summary>$O(1)$ < $O(log n)$ < $O(n)$ < $O(n log n)$ < $O(n^2)$ < $O(2^n)$ < $O(n!)$</details>
+<details><summary>Explanation:</summary>
+Remember $O(1)$, or constant time, is the slowest growing in terms of time complexity and  $O(n!)$, or factorial time, is the fastest growing.</details>
 
+#### What is the asymptotic representation of the following time complexity: $O(2n^3 + .5n^2 + 1000n)$
+- [ ] $O(2n^3)$
+- [ ] $O(n^3 + n^2 + n)$
+- [ ] $O(1000n)$
+- [ ] $O(n^3)$
+- [ ] $O(2n^3 + .5n^2 + 1000n)$
+- [ ] $O(.5n^2)$
 
-<quiz>
-  <question>
-    <p>What is the asymptotic representation of the following time complexity: `O(2n^3 + .5n^2 + 1000n)`</p>
-    <answer>`O(2n^3)`</answer>
-    <answer>`O(n^3 + n^2 + n)`</answer>
-    <answer>`O(1000n)`</answer>
-    <answer correct>`O(n^3)`</answer>
-    <answer>`O(2n^3 + .5n^2 + 1000n)`</answer>
-    <answer>`O(.5n^2)`</answer>
-    <explanation>Ignoring the constants, we get `n^3 + n^2 + n`.  `n^3` will dominate the other terms and therefore is the asymptotic representation.</explanation>
-  </question>
-</quiz>
+<details><summary>Answer:</summary>$O(n^3)$</details>
+<details><summary>Explanation:</summary>Ignoring the constants, we get $n^3 + n^2 + n$.  $n^3$ will dominate the other terms and therefore is the asymptotic representation.</details>
 
+#### Which of the following time complexities is linearithmic?
+- [ ] $O(n^2)$
+- [ ] $O(n!)$
+- [ ] $O(2^n)$
+- [ ] $O(n log n)$
+- [ ] $O(n)$
 
-<quiz>
-  <question>
-    <p>Which of the following time complexities is linearithmic?</p>
-    <answer>`O(n^2)`</answer>
-    <answer>`O(n!)`</answer>
-    <answer>`O(2^n)`</answer>
-    <answer correct>`O(n log n)`</answer>
-    <answer>`O(n)`</answer>
-    <explanation>Remember linearithmic, or loglinear, time is `O(n log n)`. This is also the time complexity for `merge sort`, which is one of the fastest comparison sorts. </explanation>
-  </question>
-</quiz>
-
+<details><summary>Answer:</summary>$O(n log n)$</details>
+<details><summary>Explanation:</summary>Remember linearithmic, or loglinear, time is $O(n log n)$. This is also the time complexity for $merge sort$, which is one of the fastest comparison sorts. </details>
 
 ```ruby
   def max_squared_value(arr)
@@ -57,29 +48,24 @@
     max
   end
 ```
+#### What is the time complexity of the above function?
+- [ ] $O(n log n)$
+- [ ] $O(n^2)$
+- [ ] $O(n)$
+- [ ] $O(n!)$
+- [ ] $O(1)$
 
-<quiz>
-  <question>
-    <p>What is the time complexity of the above function?</p>
-    <answer>`O(n log n)`</answer>
-    <answer correct>`O(n^2)`</answer>
-    <answer>`O(n)`</answer>
-    <answer>`O(n!)`</answer>
-    <answer>`O(1)`</answer>
-    <explanation>We are iterating over the input array of `n` elements. For each of those `n` elements, we do work that involves another iteration over the entire input array. In other words, for each of the `n` elements, we do `n` amount of work, which gives us `O(n^2)`.</explanation>
-  </question>
-</quiz>
+<details><summary>Answer:</summary>$O(n^2)$</details>
+<details><summary>Explanation:</summary>We are iterating over the input array of $n$ elements. For each of those $n$ elements, we do work that involves another iteration over the entire input array. In other words, for each of the $n$ elements, we do $n$ amount of work, which gives us $O(n^2)$.</details>
 
+#### What is the time complexity of ruby's `Array#permutation` method? **Note:** you do not need to look at the Ruby source code to answer this question.  Remember that Big-O notation is concerned with how runtime grows relative to the size of the input!</p>
+- [ ] $O(n*log(n))$
+- [ ] $O(n^2)$
+- [ ] $O(n)$
+- [ ] $O(n!)$
+- [ ] $O(1)$
 
+<details><summary>Answer:</summary>$O(n!)$</details>
+<details><summary>Explanation:</summary>
 
-<quiz>
-  <question>
-    <p>What is the time complexity of ruby's `Array#permutation` method? **Note:** you do not need to look at the Ruby source code to answer this question.  Remember that Big-O notation is concerned with how runtime grows relative to the size of the input!</p>
-    <answer>`O(n*log(n))`</answer>
-    <answer>`O(n^2)`</answer>
-    <answer>`O(n)`</answer>
-    <answer correct>`O(n!)`</answer>
-    <answer>`O(1)`</answer>
-    <explanation>Whenever you have a problem where you are creating permutations, you are dealing with `factorial` time complexity. E.g., if you call the `Array#permutation` method of an array with the length of 3, then 3! permutations would be returned (6 permutations total). Increasing the length to 4 would then return 24 total permutations, or 4!.</explanation>
-  </question>
-</quiz>
\ No newline at end of file
+Whenever you have a problem where you are creating permutations, you are dealing with $factorial$ time complexity. E.g., if you call the `Array#permutation` method of an array with the length of 3, then 3! permutations would be returned (6 permutations total). Increasing the length to 4 would then return 24 total permutations, or 4!.</details>
\ No newline at end of file
diff --git a/ruby/quizzes/data_structures.md b/ruby/quizzes/data_structures.md
index 6912e95..18e5b2c 100644
--- a/ruby/quizzes/data_structures.md
+++ b/ruby/quizzes/data_structures.md
@@ -1,16 +1,13 @@
 # Data Structures Quiz
 
-<quiz>
-  <question>
-    <p>LIFO (last-in-first-out) describes the behavior of which of the following?</p>
-    <answer>Queue</answer>
-    <answer>Set</answer>
-    <answer correct>Stack</answer>
-    <answer>Map</answer>
-    <explanation>When you stack things on top of each other, you have to remove the item off the top first. We can remove the item at the bottom until all of the other items on top of it have been removed.  So the first thing that goes in is actually the last thing that comes out.</explanation>
-  </question>
-</quiz>
+#### LIFO (last-in-first-out) describes the behavior of which of the following?
+- [ ] Queue
+- [ ] Set
+- [ ] Stack
+- [ ] Map
 
+<details><summary>Answer:</summary>Stack</details>
+<details><summary>Explanation:</summary>When you stack things on top of each other, you have to remove the item off the top first. We can remove the item at the bottom until all of the other items on top of it have been removed.  So the first thing that goes in is actually the last thing that comes out.</details>
 
 ```ruby
         N
@@ -22,27 +19,21 @@
   N
 ```
 
-<quiz>
-  <question>
-    <p>Is the above graph a binary tree?</p>
-    <answer>No</answer>
-    <answer correct>Yes</answer>
-    <explanation>A binary tree is a graph with the constrant that a node can have at most two children.</explanation>
-  </question>
-</quiz>
+#### Is the above graph a binary tree?
+- [ ] No
+- [ ] Yes
 
+<details><summary>Answer:</summary>Yes</details>
+<details><summary>Explanation:</summary>A binary tree is a graph with the constrant that a node can have at most two children.</details>
 
-<quiz>
-  <question>
-    <p>BFS (breadth first search) uses which of the following ADTs?</p>
-    <answer correct>Queue</answer>
-    <answer>Set</answer>
-    <answer>Stack</answer>
-    <answer>Map</answer>
-    <explanation>As we are looking at each node, we want to add their children to our list of nodes to look at.  A queue allows us to utilize FIFO (first in first out) so that the order in which the nodes are added to our list is the order in which they will be dealt with.</explanation>
-  </question>
-</quiz>
+#### BFS (breadth first search) uses which of the following ADTs?
+- [ ] Queue
+- [ ] Set
+- [ ] Stack
+- [ ] Map
 
+<details><summary>Answer:</summary>Queue</details>
+<details><summary>Explanation:</summary>As we are looking at each node, we want to add their children to our list of nodes to look at.  A queue allows us to utilize FIFO (first in first out) so that the order in which the nodes are added to our list is the order in which they will be dealt with.</details>
 
 ```ruby
         1   
@@ -54,17 +45,14 @@
   4   7   8
 ```
 
-<quiz>
-  <question>
-    <p>If we used DFS to try and find the node with value 6 in the graph above, what is a possible ordering of nodes that would be visited?</p>
-    <answer>1-2-5-3-6</answer>
-    <answer correct>1-2-3-4-5-6</answer>
-    <answer>4-3-2-1-7-8-6</answer>
-    <answer>8-7-4-9-6</answer>
-    <explanation>For DFS, we will look at a node, and then look at it's first child, and then that nodes first child and so on until we hit a leaf node or find the node we are searching for.  When we hit a leaf node, we will begin popping off the stack of recursive calls (going back up the tree a level at a time) and looking at the next child for that node. Once we find the node we are looking for, we start popping off the stack of recursive calls returning the node we found that has the value we are looking for.</explanation>
-  </question>
-</quiz>
+#### If we used DFS to try and find the node with value 6 in the graph above, what is a possible ordering of nodes that would be visited?
+- [ ] 1-2-5-3-6
+- [ ] 1-2-3-4-5-6
+- [ ] 4-3-2-1-7-8-6
+- [ ] 8-7-4-9-6
 
+<details><summary>Answer:</summary>1-2-3-4-5-6</details>
+<details><summary>Explanation:</summary>For DFS, we will look at a node, and then look at it's first child, and then that nodes first child and so on until we hit a leaf node or find the node we are searching for.  When we hit a leaf node, we will begin popping off the stack of recursive calls (going back up the tree a level at a time) and looking at the next child for that node. Once we find the node we are looking for, we start popping off the stack of recursive calls returning the node we found that has the value we are looking for.</details>
 
 ```ruby
         D   
@@ -76,15 +64,15 @@
   H   F   B
 ```
 
-<quiz>
-  <question>
-    <p>Which node in the above graph is the root?</p>
-    <answer>`A`</answer>
-    <answer>`B`</answer>
-    <answer correct>`D`</answer>
-    <answer>`F`</answer>
-    <answer>`H`</answer>
-    <answer>`I`</answer>
-    <explanation>The root node refers to the top most node that has no parent node.</explanation>
-  </question>
-</quiz>
+#### Which node in the above graph is the root?
+- [ ] `A`
+- [ ] `B`
+- [ ] `D`
+- [ ] `F`
+- [ ] `H`
+- [ ] `I`
+
+<details><summary>Answer:</summary>
+
+`D`</details>
+<details><summary>Explanation:</summary>The root node refers to the top most node that has no parent node.</details>
diff --git a/ruby/quizzes/git.md b/ruby/quizzes/git.md
index 4794788..6d1ec1f 100644
--- a/ruby/quizzes/git.md
+++ b/ruby/quizzes/git.md
@@ -1,47 +1,49 @@
 # Git Quiz
 
-<quiz>
-  <question>
-    <p>I want to push changes in my workspace to a remote repository. Which of the following outlines the correct workflow for pushing local changes to a remote repo?</p>
-    <answer correct>workspace -> index (staging area) -> local repository -> upstream repository</answer>
-    <answer>workspace -> local repository -> index (staging area) -> upstream repository</answer>
-    <answer>local repository -> workspace -> index (staging area) -> upstream repository</answer>
-    <explanation>We make changes to our local workspace, then we need to stage the changes so that they can be commited to our local repository (the hidden .git directory in our workspace) and then we can push them to the upstream remote repository.</explanation>
-  </question>
-</quiz>
-
-
-<quiz>
-  <question>
-    <p>How would you create a new branch and switch to it at the same time?</p>
-    <answer>`git -b checkout`</answer>
-    <answer>`git branch`</answer>
-    <answer correct>`git checkout -b`</answer>
-    <answer>`git branch -co`</answer>
-    <explanation>`git checkout -b` will do both for us! Instead of having to run `git branch <branch-name>` and then `git checkout <branch-name>`</explanation>
-  </question>
-</quiz>
-
-
-<quiz>
-  <question>
-    <p>Oh no! We've messed up and coded unwanted changes to our local project! How can we go back to a previous commit and get rid of the unwanted changes?</p>
-    <answer>`git rollback --soft`</answer>
-    <answer>`git undo HEAD`</answer>
-    <answer correct>`git reset --hard`</answer>
-    <answer>`git revert HEAD`</answer>
-    <explanation>`git reset --hard` will will wipe out all tracked changes back to the most recent commit.</explanation>
-  </question>
-</quiz>
-
-
-<quiz>
-  <question>
-    <p>Our remote and local repositories have gotten so out of alignment that we just want to ignore any conflicts and push our local code up to remote. How would we do this?</p>
-    <answer correct>`git push -f`</answer>
-    <answer>`git push`</answer>
-    <answer>`git force push`</answer>
-    <answer>`git push -u`</answer>
-    <explanation>The `-f` flag is short for `--force` which overrides any conflicts our local repo has with the remote repo.</explanation>
-  </question>
-</quiz>
\ No newline at end of file
+#### I want to push changes in my workspace to a remote repository. Which of the following outlines the correct workflow for pushing local changes to a remote repo?</p>
+- [ ] workspace -> index (staging area) -> local repository -> upstream repository</answer>
+- [ ] workspace -> local repository -> index (staging area) -> upstream repository</answer>
+- [ ] local repository -> workspace -> index (staging area) -> upstream repository</answer>
+    
+<details><summary>Answer:</summary>workspace -> index (staging area) -> local repository -> upstream repository</details>
+<details><summary>Explanation:</summary>
+
+We make changes to our local workspace, then we need to stage the changes so that they can be commited to our local repository (the hidden .git directory in our workspace) and then we can push them to the upstream remote repository.</details>
+
+#### How would you create a new branch and switch to it at the same time?</p>
+- [ ] `git -b checkout`</answer>
+- [ ] `git branch`</answer>
+- [ ] `git checkout -b`</answer>
+- [ ] `git branch -co`</answer>
+
+<details><summary>Answer:</summary>
+
+`git checkout -b`</details>
+<details><summary>Explanation:</summary>
+
+`git checkout -b` will do both for us! Instead of having to run `git branch <branch-name>` and then `git checkout <branch-name>`</details>
+
+#### Oh no! We've messed up and coded unwanted changes to our local project! How can we go back to a previous commit and get rid of the unwanted changes?</p>
+- [ ] `git rollback --soft`</answer>
+- [ ] `git undo HEAD`</answer>
+- [ ] `git reset --hard`</answer>
+- [ ] `git revert HEAD`</answer>
+
+<details><summary>Answer:</summary>
+
+`git reset --hard`</details>
+<details><summary>Explanation:</summary>
+
+`git reset --hard` will will wipe out all tracked changes back to the most recent commit.</details>
+
+#### Our remote and local repositories have gotten so out of alignment that we just want to ignore any conflicts and push our local code up to remote. How would we do this?</p>
+- [ ] `git push -f`</answer>
+- [ ] `git push`</answer>
+- [ ] `git force push`</answer>
+- [ ] `git push -u`</answer>
+<details><summary>Answer:</summary>
+
+`git push -f`</answer></details>
+<details><summary>Explanation:</summary>
+
+The `-f` flag is short for `--force` which overrides any conflicts our local repo has with the remote repo.</details>
\ No newline at end of file
diff --git a/ruby/quizzes/lru_cache.md b/ruby/quizzes/lru_cache.md
index 4162491..e7ab979 100644
--- a/ruby/quizzes/lru_cache.md
+++ b/ruby/quizzes/lru_cache.md
@@ -8,48 +8,52 @@
   end
 ```
 
-<quiz>
-  <question>
-    <p>Is the above function a hashing function?</p>
-    <answer>Yes</answer>
-    <answer correct>No</answer>
-    <explanation>A hashing function must be **deterministic**: the same input should always produce the same output, which won't happen if the output relies on a randomly generated number!</explanation>
-  </question>
-</quiz>
-
-
-<quiz>
-  <question>
-    <p>In a linked list, what is the time complexity for accessing the nth element?</p>
-    <answer>`O(1)`</answer>
-    <answer>`O(log n)`</answer>
-    <answer correct>`O(n)`</answer>
-    <answer>`O(n log n)`</answer>
-    <answer>`O(n^2)`</answer>
-    <explanation>Unlike with an array or hash--which allow access to the nth element by index and key, respectively--accessing the nth element in a linked list requires following links from the first element to each successive element until reaching the nth one, an `O(n)` operation.</explanation>
-  </question>
-</quiz>
+#### Is the above function a hashing function?</p>
+- [ ] Yes
+- [ ] No
+
+<details><summary>Answer:</summary>
+
+No</details>
+<details><summary>Explanation:</summary>
+
+A hashing function must be **deterministic**: the same input should always produce the same output, which won't happen if the output relies on a randomly generated number!</details>
+
+#### In a linked list, what is the time complexity for accessing the nth element?</p>
+- [ ] $O(1)$
+- [ ] $O(log n)$
+- [ ] $O(n)$
+- [ ] $O(n log n)$
+- [ ] $O(n^2)$
+
+<details><summary>Answer:</summary>
+
+$O(n)$</details>
+<details><summary>Explanation:</summary>
+
+Unlike with an array or hash--which allow access to the nth element by index and key, respectively--accessing the nth element in a linked list requires following links from the first element to each successive element until reaching the nth one, an $O(n)$ operation.</details>
 
 ```ruby
   {4,78,12,56,44,78,15}
 ```
+#### Is the above a set?</p>
+- [ ] Yes
+- [ ] No
+<details><summary>Answer:</summary>
+
+No</details>
+<details><summary>Explanation:</summary>
+
+A set is a data type that stores *unique* items.</details>
+
+#### An array is an example of which of the following? (Select all that apply.)</p>
+- [ ] Abstract Data Type
+- [ ] Algorithm
+- [ ] Data Structure
+- [ ] Transfer Function
+<details><summary>Answer:</summary>
+
+Data Structure</details>
+<details><summary>Explanation:</summary>
 
-<quiz>
-  <question>
-    <p>Is the above a set?</p>
-    <answer>Yes</answer>
-    <answer correct>No</answer>
-    <explanation>A set is a data type that stores *unique* items.</explanation>
-  </question>
-</quiz>
-
-<quiz>
-  <question multiple>
-    <p>An array is an example of which of the following? (Select all that apply.)</p>
-    <answer>Abstract Data Type</answer>
-    <answer>Algorithm</answer>
-    <answer correct>Data Structure</answer>
-    <answer>Transfer Function</answer>
-    <explanation>An array is an example of a data structure! :)</explanation>
-  </question>
-</quiz>
+An array is an example of a data structure! :)</details>
\ No newline at end of file
diff --git a/ruby/quizzes/oop_1.md b/ruby/quizzes/oop_1.md
index 29bbb35..cbbfd98 100644
--- a/ruby/quizzes/oop_1.md
+++ b/ruby/quizzes/oop_1.md
@@ -27,19 +27,18 @@
   west_coast_swing = Swing.new("West Coast")
 ```
 
-<quiz>
-  <question>
-    <p>Consider the above code. What are the respective return values from calling `bolshoi.style` and `west_coast_swing.style`?</p>
-    <answer>`"Tap"`, `"Tap"`</answer>
-    <answer>`"Ballet"`, `"Tap"`</answer>
-    <answer correct>`"Ballet"`, `"West Coast"`</answer>
-    <answer>`"Vaganova"`, `"Ballet"`</answer>
-    <answer>`"Vaganova"`, `"West Coast"`</answer>
-    <explanation>When called without any arguments (as in `Swing#initialize`), the `super` keyword will take all the arguments passed in to the current method and pass them as arguments to the parent class's version of the method. So `west_coast_swing` will have its `@style` set to "West Coast", i.e., the argument originally passed in to `Swing#initialize`. The `Ballet` class, however, does specify an argument for `super` to pass to its parent `Dance` class: "Ballet". `bolshoi`'s `@style` will accordingly be set to "Ballet". </explanation>
-  </question>
-</quiz>
+#### Consider the above code. What are the respective return values from calling `bolshoi.style` and `west_coast_swing.style`?</p>
+- [ ] `"Tap"`, `"Tap"`
+- [ ] `"Ballet"`, `"Tap"`
+- [ ] `"Ballet"`, `"West Coast"`
+- [ ] `"Vaganova"`, `"Ballet"`
+- [ ] `"Vaganova"`, `"West Coast"`
+<details><summary>Answer:</summary>
 
+No`"Ballet"`, `"West Coast"`</details>
+<details><summary>Explanation:</summary>
 
+When called without any arguments (as in `Swing#initialize`), the `super` keyword will take all the arguments passed in to the current method and pass them as arguments to the parent class's version of the method. So `west_coast_swing` will have its `@style` set to "West Coast", i.e., the argument originally passed in to `Swing#initialize`. The `Ballet` class, however, does specify an argument for `super` to pass to its parent `Dance` class: "Ballet". `bolshoi`'s `@style` will accordingly be set to "Ballet". </details>
 
 ```ruby
   class EngineStalledError < StandardError
@@ -64,18 +63,17 @@
   end
 ```
 
-<quiz>
-  <question>
-    <p>Consider the above example. The first time `drive_car` is called, an EngineStalledError is raised! What happens next?</p>
-    <answer>The program outputs `"Rescued from engine stalled!"` then `"Car stopped."`</answer>
-    <answer>An uncaught error is thrown</answer>
-    <answer correct>The program outputs `"Rescued from engine stalled!"` then retries running the code block </answer>
-    <answer>The program outputs `"Car stopped."`</answer>
-    <explanation>After rescuing the `EngineStalledError` this code block will hit the `retry` keyword.</explanation>
-  </question>
-</quiz>
+#### Consider the above example. The first time `drive_car` is called, an EngineStalledError is raised! What happens next?</p>
+- [ ] The program outputs `"Rescued from engine stalled!"` then `"Car stopped."`
+- [ ] An uncaught error is thrown
+- [ ] The program outputs `"Rescued from engine stalled!"` then retries running the code block 
+- [ ] The program outputs `"Car stopped."`
+<details><summary>Answer:</summary>
 
+The program outputs `"Rescued from engine stalled!"` then retries running the code block </details>
+<details><summary>Explanation:</summary>
 
+After rescuing the `EngineStalledError` this code block will hit the `retry` keyword.</details>
 
 ```ruby
   class BoxOffice
@@ -101,27 +99,29 @@
   tkts = BoxOffice.new(2000, "Rent")
 ```
 
-<quiz>
-  <question>
-    <p>Consider the above code. Which of the following is a valid way to increase the number of `tkts` tickets sold by 1?</p>
-    <answer>`tkts.update_tickets_sold`</answer>
-    <answer>`BoxOffice.update_tickets_sold`</answer>
-    <answer correct>`tkts.sell_ticket`</answer>
-    <answer>`tkts.tickets_sold += 1`</answer>
-    <answer>`BoxOffice.sell_ticket`</answer>
-    <explanation>To increase the number of tickets sold for the `tkts` instance of the `BoxOffice` class, you just need to call the `sell_ticket` method on that instance.</explanation>
-  </question>
-</quiz>
-
-
-<quiz>
-  <question>
-    <p>You are writing a program that makes sandwiches. Each sandwich has a protein, a condiment, and two slices of bread. There are different types of proteins, condiments, and breads, but within each of those categories, the different types are functionally all the same. According to the principles of Object-Oriented Programming, what classes should you create for your program?</p>
-    <answer>Sandwich, Bread, RyeBread, SourDoughBread, WholeWheatBread, Protein, 
-    Chicken, Tofu, Seitan, Turkey, Condiment, Mustard, Ketchup, Mayo</answer>
-    <answer correct>Sandwich, Bread, Protein, Condiment</answer>
-    <answer>Sandwich</answer>
-    <answer>Sandwich, Bread, Protein, Mustard, Ketchup, Aioli</answer>
-    <explanation>When taking an OOP approach, you typically want to break your program down into base classes (like `Bread`) that have a single responsibility / reason to change. If Sandwich were the only class, it would have to change whenever you needed to update the functionality of proteins, condiments, or bread, thus violating the preceding principle. At the same time, you don't need to break proteins, condiments, and bread down further because all of their different types share the same functionality.</explanation>
-  </question>
-</quiz>
\ No newline at end of file
+#### Consider the above code. Which of the following is a valid way to increase the number of `tkts` tickets sold by 1?</p>
+- [ ] `tkts.update_tickets_sold`
+- [ ] `BoxOffice.update_tickets_sold`
+- [ ] `tkts.sell_ticket`
+- [ ] `tkts.tickets_sold += 1`
+- [ ] `BoxOffice.sell_ticket`
+<details><summary>Answer:</summary>
+
+`tkts.sell_ticket`</details>
+<details><summary>Explanation:</summary>
+
+To increase the number of tickets sold for the `tkts` instance of the `BoxOffice` class, you just need to call the `sell_ticket` method on that instance.</details>
+
+
+#### You are writing a program that makes sandwiches. Each sandwich has a protein, a condiment, and two slices of bread. There are different types of proteins, condiments, and breads, but within each of those categories, the different types are functionally all the same. According to the principles of Object-Oriented Programming, what classes should you create for your program?</p>
+- [ ] Sandwich, Bread, RyeBread, SourDoughBread, WholeWheatBread, Protein, 
+- [ ] Chicken, Tofu, Seitan, Turkey, Condiment, Mustard, Ketchup, Mayo
+- [ ] Sandwich, Bread, Protein, Condiment
+- [ ] Sandwich
+- [ ] Sandwich, Bread, Protein, Mustard, Ketchup, Aioli
+<details><summary>Answer:</summary>
+
+Sandwich, Bread, Protein, Condiment</details>
+<details><summary>Explanation:</summary>
+
+When taking an OOP approach, you typically want to break your program down into base classes (like `Bread`) that have a single responsibility / reason to change. If Sandwich were the only class, it would have to change whenever you needed to update the functionality of proteins, condiments, or bread, thus violating the preceding principle. At the same time, you don't need to break proteins, condiments, and bread down further because all of their different types share the same functionality.</details>
\ No newline at end of file
diff --git a/ruby/quizzes/oop_2.md b/ruby/quizzes/oop_2.md
index 79fee69..f973b2a 100644
--- a/ruby/quizzes/oop_2.md
+++ b/ruby/quizzes/oop_2.md
@@ -34,18 +34,20 @@
   marin = County.new
 ```
 
-<quiz>
-  <question>
-    <p>Consider the above code. What are the respective return values from calling `nyc.state`, `oaktown.state`, and `marin.state`?</p>
-    <answer>`"New York"`, `"California"`, `"California"`</answer>
-    <answer>`"New York City"`, `"California"`, `"Marin"`</answer>
-    <answer correct>`"New York"`, `500000`, `"California"`</answer>
-    <answer>`"New York City"`, `"California"`, `NoMethodError`</answer>
-    <answer>`"California"`, `"California"`, `"California"`</answer>
-    <explanation>`City#initialize` explicitly passes its `state` parameter (here, `"New York"`) to `super`. `Town#initialize`, in contrast, just calls `super`, which passes along all of `Town#initialize`'s incoming arguments (here, `500000`) to `Municipality#initialize`. (To avoid passing along its arguments and have `super` apply the default argument of `"California"`, `Town#initialize` would need to indicate explicitly that it was calling `super` without any arguments, i.e., `super()`.) Finally, since the `County` class does not have a defined initialize method, calling `new`  on `County` will run the parent class's `initialize` method, thereby setting `state` to the default value of `"California"`. 
-    </explanation>
-  </question>
-</quiz>
+#### Consider the above code. What are the respective return values from calling `nyc.state`, `oaktown.state`, and `marin.state`?</p>
+- [ ] `"New York"`, `"California"`, `"California"`
+- [ ] `"New York City"`, `"California"`, `"Marin"`
+- [ ] `"New York"`, `500000`, `"California"`
+- [ ] `"New York City"`, `"California"`, `NoMethodError`
+- [ ] `"California"`, `"California"`, `"California"`
+
+<details><summary>Answer:</summary>
+
+`"New York"`, `500000`, `"California"`</details>
+<details><summary>Explanation:</summary>
+
+`City#initialize` explicitly passes its `state` parameter (here, `"New York"`) to `super`. `Town#initialize`, in contrast, just calls `super`, which passes along all of `Town#initialize`'s incoming arguments (here, `500000`) to `Municipality#initialize`. (To avoid passing along its arguments and have `super` apply the default argument of `"California"`, `Town#initialize` would need to indicate explicitly that it was calling `super` without any arguments, i.e., `super()`.) Finally, since the `County` class does not have a defined initialize method, calling `new`  on `County` will run the parent class's `initialize` method, thereby setting `state` to the default value of `"California"`. 
+    </details>
 
 
 
@@ -74,16 +76,18 @@ board = Board.new
 board.add_piece([0,0], Pawn.new)
 ```
 
-<quiz>
-  <question>
-    <p>Why will the code above not add the pawn to `0, 0` as expected?</p>
-    <answer>The `*` splat operator should be used in `#add_piece` when indexing into the grid: `@grid[*pos] = piece`</answer>
-    <answer correct>`#add_piece` should call `self[pos]` rather than `@grid[pos]`</answer>
-    <answer>There should be an `attr_reader` for the `@grid` instance variable.</answer>
-    <answer>Nothing is wrong with the above code.</answer>
-    <explanation>It will not add the pawn because `@grid[pos]` in `#add_piece` resolves to `@grid[[0,0]]`, which will produce `TypeError: no implicit conversion of Array into Integer`. It produces this error because `@grid` is an `Array`, and the `Array#[]` method expects an integer as an argument, not an array (i.e., not `[0,0]`). To avoid this problem, note that the `Board#[]` and `Board#[]=` methods both expect an array as an argument (`pos`) and use that array to access `@grid` for you. `#add_piece` will accordingly add the pawn successfully if it instead calls `self[pos] = piece`.</explanation>
-  </question>
-</quiz>
+#### Why will the code above not add the pawn to `0, 0` as expected?</p>
+- [ ] The `*` splat operator should be used in `#add_piece` when indexing into the grid: `@grid[*pos] = piece`
+- [ ] `#add_piece` should call `self[pos]` rather than `@grid[pos]`
+- [ ] There should be an `attr_reader` for the `@grid` instance variable.
+- [ ] Nothing is wrong with the above code.
+
+<details><summary>Answer:</summary>
+
+`#add_piece` should call `self[pos]` rather than `@grid[pos]`</details>
+<details><summary>Explanation:</summary>
+
+It will not add the pawn because `@grid[pos]` in `#add_piece` resolves to `@grid[[0,0]]`, which will produce `TypeError: no implicit conversion of Array into Integer`. It produces this error because `@grid` is an `Array`, and the `Array#[]` method expects an integer as an argument, not an array (i.e., not `[0,0]`). To avoid this problem, note that the `Board#[]` and `Board#[]=` methods both expect an array as an argument (`pos`) and use that array to access `@grid` for you. `#add_piece` will accordingly add the pawn successfully if it instead calls `self[pos] = piece`.</details>
 
 
 
@@ -103,16 +107,18 @@ pawn_copy.position[1] = "CHANGED"
 pawn.position
 ```
 
-<quiz>
-  <question>
-    <p>Consider the above code, which uses Ruby's native `#dup` method. What will `pawn` and `pawn_copy`'s positions be? </p>
-    <answer correct>`[0, "CHANGED"]`, `[0, "CHANGED"]`</answer>
-    <answer>`[0, 1]`, `[0, "CHANGED"]`</answer>
-    <answer>`[0, 1]`, `[0, 1]`</answer>
-    <answer>`[0, "CHANGED"]`, `[0, 1]`</answer>
-    <explanation>Remember that Ruby's native `#dup` method only makes a shallow copy. This means that it copies the references stored in instance variables instead of creating new copies of the objects they reference. `pawn` and `pawn_copy` will accordingly both reference the same array, but if they both reference the same array, then changing that array in one instance will also change it in the other! To avoid this problem, you would need to create a new position array when making your second pawn.</explanation>
-  </question>
-</quiz>
+#### Consider the above code, which uses Ruby's native `#dup` method. What will `pawn` and `pawn_copy`'s positions be? </p>
+- [ ] `[0, "CHANGED"]`, `[0, "CHANGED"]`
+- [ ] `[0, 1]`, `[0, "CHANGED"]`
+- [ ] `[0, 1]`, `[0, 1]`
+- [ ] `[0, "CHANGED"]`, `[0, 1]`
+
+<details><summary>Answer:</summary>
+
+`[0, "CHANGED"]`, `[0, "CHANGED"]`</details>
+<details><summary>Explanation:</summary>
+
+Remember that Ruby's native `#dup` method only makes a shallow copy. This means that it copies the references stored in instance variables instead of creating new copies of the objects they reference. `pawn` and `pawn_copy` will accordingly both reference the same array, but if they both reference the same array, then changing that array in one instance will also change it in the other! To avoid this problem, you would need to create a new position array when making your second pawn.</details>
 
 
 
@@ -124,13 +130,15 @@ class Piece
 end
 ```
 
-<quiz>
-  <question>
-    <p>Consider the above code. How would you create and refer to this `Piece` object?</p>
-    <answer>`Piece.new`</answer>
-    <answer>`Piece.create`</answer>
-    <answer correct>`Piece.instance`</answer>
-    <answer>`Singleton.instance`</answer>
-    <explanation>The `Singleton` module allows you to have only one instance of a class. You would invoke that singular instance using `Piece.instance`. </explanation>
-  </question>
-</quiz>
\ No newline at end of file
+#### Consider the above code. How would you create and refer to this `Piece` object?</p>
+- [ ] `Piece.new`
+- [ ] `Piece.create`
+- [ ] `Piece.instance`
+- [ ] `Singleton.instance`
+
+<details><summary>Answer:</summary>
+
+`Piece.instance`</details>
+<details><summary>Explanation:</summary>
+
+The `Singleton` module allows you to have only one instance of a class. You would invoke that singular instance using `Piece.instance`. </details>
\ No newline at end of file
diff --git a/ruby/quizzes/recursion.md b/ruby/quizzes/recursion.md
index 6181d7b..aafa493 100644
--- a/ruby/quizzes/recursion.md
+++ b/ruby/quizzes/recursion.md
@@ -7,26 +7,32 @@
   end
 ```
 
-<quiz>
-  <question multiple>
-    <p>What is wrong with the above function?</p>
-    <answer>Indentation is wrong</answer>
-    <answer correct>Variable names are not descriptive</answer>
-    <answer correct>Code needs to be broken out over more lines</answer>
-    <answer>This code cannot be improved</answer>
-    <explanation>`arg1` and `arg2` don't give us any idea about what the numbers should be representing that will be passed in. Additionally, the math for `return_val` is not intuitive and should be broken up.</explanation>
-  </question>
-</quiz>
-
-
-<quiz>
-  <question multiple>
-    <p>Suppose we have a function called `args_matey` which expects 3 arguments: a string, an array, and a hash. Select each of the following that correctly passes these arguments:</p>
-    <answer correct>`args_matey('argument 1', [1,2,3,4], hash: 'is', last: 'argument')`</answer>
-    <answer correct>`args_matey('argument 1', [1,2,3,4], { hash: 'is', last: 'argument' })`</answer>
-    <explanation>As long as the hash is the last argument given in the method invocation, ruby will assume that the key value pairs are part of the expected hash. So, we don't have to include the curly braces in this scenario.</explanation>
-  </question>
-</quiz>
+#### What is wrong with the above function?</p>
+- [ ] Indentation is wrong</answer>
+- [ ] Variable names are not descriptive</answer>
+- [ ] Code needs to be broken out over more lines</answer>
+- [ ] This code cannot be improved</answer>
+
+<details><summary>Answer:</summary>
+
+- Variable names are not descriptive
+- Code needs to be broken out over more lines</details>
+<details><summary>Explanation:</summary>
+
+`arg1` and `arg2` don't give us any idea about what the numbers should be representing that will be passed in. Additionally, the math for `return_val` is not intuitive and should be broken up.</details>
+
+
+#### Suppose we have a function called `args_matey` which expects 3 arguments: a string, an array, and a hash. Select each of the following that correctly passes these arguments:</p>
+- [ ] `args_matey('argument 1', [1,2,3,4], hash: 'is', last: 'argument')`</answer>
+- [ ] `args_matey('argument 1', [1,2,3,4], { hash: 'is', last: 'argument' })`</answer>
+
+<details><summary>Answer:</summary>
+
+- `args_matey('argument 1', [1,2,3,4], hash: 'is', last: 'argument')`
+- `args_matey('argument 1', [1,2,3,4], { hash: 'is', last: 'argument' })`</details>
+<details><summary>Explanation:</summary>
+
+As long as the hash is the last argument given in the method invocation, ruby will assume that the key value pairs are part of the expected hash. So, we don't have to include the curly braces in this scenario.</details>
 
 
 ```ruby
@@ -41,17 +47,20 @@
   end
 ```
 
-<quiz>
-  <question multiple>
-    <p>Consider the above function that calculates the sum of all odd integers from 1 to n (inclusive). For which of the following test cases will the above function throw a stack overflow error?</p>
-    <answer>`add_odds(9)`</answer>
-    <answer correct>`add_odds(50000)`</answer>
-    <answer>`add_odds(123)`</answer>
-    <answer correct>`add_odds(-8)`</answer>
-    <answer>`add_odds(1)`</answer>
-    <explanation>The average computer setup will give us around 9000 stack frames before throwing a stack overflow error. With an input of 50000, our method would try to create 50000 stacks and would get cut off before it gets there. with an input of -8, our function will continue to make recursive calls and add stack frames indefinitely because we will never hit our base case which checks that `n` is equal to 1. `n` will never be equal to 1.</explanation>
-  </question>
-</quiz>
+#### Consider the above function that calculates the sum of all odd integers from 1 to n (inclusive). For which of the following test cases will the above function throw a stack overflow error?</p>
+- [ ] `add_odds(9)`</answer>
+- [ ] `add_odds(50000)`</answer>
+- [ ] `add_odds(123)`</answer>
+- [ ] `add_odds(-8)`</answer>
+- [ ] `add_odds(1)`</answer>
+<details><summary>Answer:</summary>
+
+- `add_odds(50000)`
+- `add_odds(-8)`</details>
+
+<details><summary>Explanation:</summary>
+
+The average computer setup will give us around 9000 stack frames before throwing a stack overflow error. With an input of 50000, our method would try to create 50000 stacks and would get cut off before it gets there. with an input of -8, our function will continue to make recursive calls and add stack frames indefinitely because we will never hit our base case which checks that `n` is equal to 1. `n` will never be equal to 1.</details>
 
 
 ```ruby
@@ -62,14 +71,17 @@
   end
 ```
 
-<quiz>
-  <question>
-    <p>Consider the above function, which is defined for a 1-D array of strings. This function is:</p>
-    <answer>Recursive</answer>
-    <answer correct>Iterative</answer>
-    <explanation>Each element in our array is an instance of a String. When we invoke `string.upcase` we are invoking the upcase method that is written on the String class. The `upcase` method above is written on the Array class. Therefore, we are not calling the same method inside of the `map` iteration.</explanation>
-  </question>
-</quiz>
+#### Consider the above function, which is defined for a 1-D array of strings. This function is:</p>
+- [ ] Recursive</answer>
+- [ ] Iterative</answer>
+
+<details><summary>Answer:</summary>
+
+- Iterative</details>
+
+<details><summary>Explanation:</summary>
+
+Each element in our array is an instance of a String. When we invoke `string.upcase` we are invoking the upcase method that is written on the String class. The `upcase` method above is written on the Array class. Therefore, we are not calling the same method inside of the `map` iteration.</details>
 
 
 ```ruby
@@ -80,14 +92,15 @@
   end
 ```
 
-<quiz>
-  <question>
-    <p>Consider the above function. How many stack frames are produced from calling `powers_sum(n)`? (assume n > 0)</p>
-    <answer correct>`n`</answer>
-    <answer>`n+1`</answer>
-    <answer>`2n`</answer>
-    <answer>`n^2`</answer>
-    <answer>`cannot be determined`</answer>
-    <explanation>For each recursive call, we open up one additional stack frame because we invoke `powers_sum` once for each call. We decrease our number, `n`, by 1 for each call. Therefore there will be `n` stack frames.</explanation>
-  </question>
-</quiz>
+#### Consider the above function. How many stack frames are produced from calling `powers_sum(n)`? (assume n > 0)</p>
+- [ ] `n`</answer>
+- [ ] `n+1`</answer>
+- [ ] `2n`</answer>
+- [ ] `n^2`</answer>
+- [ ] `cannot be determined`</answer>
+<details><summary>Answer:</summary>
+
+- `n`</details>
+<details><summary>Explanation:</summary>
+
+For each recursive call, we open up one additional stack frame because we invoke `powers_sum` once for each call. We decrease our number, `n`, by 1 for each call. Therefore there will be `n` stack frames.</details>
diff --git a/ruby/quizzes/reference.md b/ruby/quizzes/reference.md
index bcc0e03..5dde5f0 100644
--- a/ruby/quizzes/reference.md
+++ b/ruby/quizzes/reference.md
@@ -5,18 +5,19 @@
   arr[0] << "Foo"
   arr
 ```
-<quiz>
-  <question>
-    <p>What will be the output of the above code?</p>
-    <answer correct>`[["Foo"] ,["Foo"], ["Foo"]]`</answer>
-    <answer>`[[], [], []]`</answer>
-    <answer>`[["Foo"], [], []]`</answer>
-    <answer>`["Foo", [], []]`</answer>
-    <answer>`["Foo", "Foo", "Foo"]`</answer>
-    <answer>None of the above</answer>
-    <explanation>The three empty arrays in `arr` are all the same array in memory (same object id).  When we shovel something into the first array, all three get modified because each element in our parent array has a memory pointer to the same array.</explanation>
-  </question>
-</quiz>
+#### What will be the output of the above code?</p>
+- [ ] `[["Foo"] ,["Foo"], ["Foo"]]`
+- [ ] `[[], [], []]`
+- [ ] `[["Foo"], [], []]`
+- [ ] `["Foo", [], []]`
+- [ ] `["Foo", "Foo", "Foo"]`
+- [ ] None of the above
+<details><summary>Answer:</summary>
+
+- `[["Foo"] ,["Foo"], ["Foo"]]`</details>
+<details><summary>Explanation:</summary>
+
+The three empty arrays in `arr` are all the same array in memory (same object id).  When we shovel something into the first array, all three get modified because each element in our parent array has a memory pointer to the same array.</details>
 
 
 
@@ -26,18 +27,19 @@
   arr
 ```
 
-<quiz>
-  <question>
-    <p>What will be the output of the above code?</p>
-    <answer>`[[], [], []]`</answer>
-    <answer correct>`[["Foo"], [], []]`</answer>
-    <answer>`["Foo", [], []]`</answer>
-    <answer>`["Foo", "Foo", "Foo"]`</answer>
-    <answer>`[["Foo"] ,["Foo"], ["Foo"]]`</answer>
-    <answer>None of the above</answer>
-    <explanation>Passing a block to `Array.new` creates a new array with a different object id for every element in `arr`.</explanation>
-  </question>
-</quiz>
+#### What will be the output of the above code?</p>
+- [ ] `[[], [], []]`
+- [ ] `[["Foo"], [], []]`
+- [ ] `["Foo", [], []]`
+- [ ] `["Foo", "Foo", "Foo"]`
+- [ ] `[["Foo"] ,["Foo"], ["Foo"]]`
+- [ ] None of the above
+<details><summary>Answer:</summary>
+
+- `[["Foo"], [], []]`</details>
+<details><summary>Explanation:</summary>
+
+Passing a block to `Array.new` creates a new array with a different object id for every element in `arr`.</details>
 
 
 
@@ -50,18 +52,20 @@
   p x
 ```
 
-<quiz>
-  <question>
-    <p>What will be the output of the above code?</p>
-    <answer>`42`</answer>
-    <answer correct>`15`</answer>
-    <answer>`"x"`</answer>
-    <answer>`10`</answer>
-    <answer>`nil`</answer>
-    <answer>None of the above</answer>
-    <explanation>When printing `x`, ruby will check the current scope for a variable named `x`.  In this case, x is set to 15.  When you define a function `def` you are creating a new scope that is fully contained by the method definition.  Ruby will not look into that scope for a variable named `x`.</explanation>
-  </question>
-</quiz>
+#### What will be the output of the above code?</p>
+- [ ] `42`
+- [ ] `15`
+- [ ] `"x"`
+- [ ] `10`
+- [ ] `nil`
+- [ ] None of the above
+
+<details><summary>Answer:</summary>
+
+- `15`</details>
+<details><summary>Explanation:</summary>
+
+When printing `x`, ruby will check the current scope for a variable named `x`.  In this case, x is set to 15.  When you define a function `def` you are creating a new scope that is fully contained by the method definition.  Ruby will not look into that scope for a variable named `x`.</details>
 
 
 
@@ -74,32 +78,38 @@
   p x
 ```
 
-<quiz>
-  <question>
-    <p>What will be the output of the above code?</p>
-    <answer correct>`["Fancy Feast"]`</answer>
-    <answer>`"Fancy Feast"`</answer>
-    <answer>`[]`</answer>
-    <answer>`nil`</answer>
-    <answer>`["Fancy", "Feast"]`</answer>
-    <answer>None of the above</answer>
-    <explanation>Since we are passing the array, `x`, into the invocation of `foo`, the local variable `x` inside the scope of the `foo` method has a pointer to the same array in the outter scope.</explanation>
-  </question>
-</quiz>
+#### What will be the output of the above code?</p>
+- [ ] `["Fancy Feast"]`
+- [ ] `"Fancy Feast"`
+- [ ] `[]`
+- [ ] `nil`
+- [ ] `["Fancy", "Feast"]`
+- [ ] None of the above
+
+<details><summary>Answer:</summary>
+
+- `["Fancy Feast"]`</details>
+<details><summary>Explanation:</summary>
 
+Since we are passing the array, `x`, into the invocation of `foo`, the local variable `x` inside the scope of the `foo` method has a pointer to the same array in the outter scope.</details>
 
 
 ```ruby
   game.board[pos].revealed = true if !guess && game.board[pos] && game.board[pos].revealed == false
 ```
 
-<quiz>
-  <question multiple>
-    <p>What's wrong with the above line of code?</p>
-    <answer correct>Long method chain suggests Law of Demeter violation</answer>
-    <answer correct>`if !condition` is not stylistic ruby</answer>
-    <answer correct>Objects are tightly coupled</answer>
-    <answer correct>Code is not DRY</answer>
-    <explanation>We are chaining too many methods.  The `!if` should be changed to `unless` when possible. We are relying on the `board` information on the `game` for every call instead of being able to call a method directly on the game. And the `game.board[pos]` is repeated many times making it complicated to understand right off the bat.</explanation>
-  </question>
-</quiz>
+#### What's wrong with the above line of code?</p>
+- [ ] Long method chain suggests Law of Demeter violation
+- [ ] `if !condition` is not stylistic ruby
+- [ ] Objects are tightly coupled
+- [ ] Code is not DRY
+
+<details><summary>Answer:</summary>
+
+- Long method chain suggests Law of Demeter violation
+- `if !condition` is not stylistic ruby
+- Objects are tightly coupled
+- Code is not DRY</details>
+<details><summary>Explanation:</summary>
+
+We are chaining too many methods.  The `!if` should be changed to `unless` when possible. We are relying on the `board` information on the `game` for every call instead of being able to call a method directly on the game. And the `game.board[pos]` is repeated many times making it complicated to understand right off the bat.</details>
diff --git a/ruby/quizzes/rspec_tdd.md b/ruby/quizzes/rspec_tdd.md
index 8f859e8..5da076e 100644
--- a/ruby/quizzes/rspec_tdd.md
+++ b/ruby/quizzes/rspec_tdd.md
@@ -20,15 +20,17 @@
   end
 ```
 
-<quiz>
-  <question>
-    <p>What is wrong with the above setup for testing with RSpec?</p>
-    <answer>Spec file should say `require_relative './lib/hello_world'` instead of `require 'hello_world'`.</answer>
-    <answer correct>`hello_world_spec.rb` should live in a `spec` directory adjacent to the `lib` directory.</answer>
-    <answer>`hello_world_spec` should be a `.rspec` file instead of `.rb`.</answer>
-    <explanation>Your spec files should live in a `spec` directory adjacent to your `lib` directory that contains what is being tested.</explanation>
-  </question>
-</quiz>
+#### What is wrong with the above setup for testing with RSpec?</p>
+- [ ] Spec file should say `require_relative './lib/hello_world'` instead of `require 'hello_world'`.
+- [ ] `hello_world_spec.rb` should live in a `spec` directory adjacent to the `lib` directory.
+- [ ] `hello_world_spec` should be a `.rspec` file instead of `.rb`.
+
+<details><summary>Answer:</summary>
+
+- `hello_world_spec.rb` should live in a `spec` directory adjacent to the `lib` directory.</details>
+<details><summary>Explanation:</summary>
+
+Your spec files should live in a `spec` directory adjacent to your `lib` directory that contains what is being tested.</details>
 
 
 ```ruby
@@ -39,16 +41,19 @@
   end
 ```
 
-<quiz>
-  <question>
-    <p>What is wrong with the above spec's syntax?</p>
-    <answer correct>An `expect` statement must be nested within an `it` block.</answer>
-    <answer>A `context` block cannot be nested within a `describe` block.</answer>
-    <answer>`to eq('hi')` should read `to_eq('hi')`.</answer>
-    <answer>Nothing is wrong with the spec's syntax.</answer>
-    <explanation>Remember that RSpec proper syntax!</explanation>
-  </question>
-</quiz>
+#### What is wrong with the above spec's syntax?</p>
+- [ ] An `expect` statement must be nested within an `it` block.
+- [ ] A `context` block cannot be nested within a `describe` block.
+- [ ] `to eq('hi')` should read `to_eq('hi')`.
+- [ ] Nothing is wrong with the spec's syntax.
+
+<details><summary>Answer:</summary>
+
+- An `expect` statement must be nested within an `it` block.</details>
+
+<details><summary>Explanation:</summary>
+
+Remember that RSpec proper syntax!</details>
 
 
 
@@ -65,16 +70,19 @@
   end
 ```
 
-<quiz>
-  <question>
-    <p>What is wrong with the above spec's syntax?</p>
-    <answer>`Robot` should be a string.</answer>
-    <answer>A `describe` block cannot be nested within a `describe` block.</answer>
-    <answer>`to be true` should be `to_be true`.</answer>
-    <answer correct>Nothing is wrong with the spec's syntax.</answer>
-    <explanation>This spec looks good!</explanation>
-  </question>
-</quiz>
+#### What is wrong with the above spec's syntax?</p>
+- [ ] `Robot` should be a string.
+- [ ] A `describe` block cannot be nested within a `describe` block.
+- [ ] `to be true` should be `to_be true`.
+- [ ] Nothing is wrong with the spec's syntax.
+
+<details><summary>Answer:</summary>
+
+- Nothing is wrong with the spec's syntax.</details>
+
+<details><summary>Explanation:</summary>
+
+This spec looks good!</details>
 
 
 
@@ -88,16 +96,19 @@ describe '#error_raiser' do
 end
 ```
 
-<quiz>
-  <question>
-    <p>What is wrong with the above spec's syntax?</p>
-    <answer>The pending spec is invalid.</answer>
-    <answer correct>`expect(error_raiser('raise'))` should be `expect {error_raiser('raise')}`.</answer>
-    <answer>`ArgumentError` should be a string.</answer>
-    <answer>Nothing is wrong with the spec's syntax.</answer>
-    <explanation>Remember to wrap any spec expected to raise an error in curly braces. This will effectively create a `begin` & `rescue` block for you.</explanation>
-  </question>
-</quiz>
+#### What is wrong with the above spec's syntax?</p>
+- [ ] The pending spec is invalid.
+- [ ] `expect(error_raiser('raise'))` should be `expect {error_raiser('raise')}`.
+- [ ] `ArgumentError` should be a string.
+- [ ] Nothing is wrong with the spec's syntax.
+
+<details><summary>Answer:</summary>
+
+- `expect(error_raiser('raise'))` should be `expect {error_raiser('raise')}`.</details>
+
+<details><summary>Explanation:</summary>
+
+Remember to wrap any spec expected to raise an error in curly braces. This will effectively create a `begin` & `rescue` block for you.</details>
 
 
 
@@ -126,11 +137,13 @@ describe Dog do
 end
 ```
 
-<quiz>
-  <question>
-    <p>Consider the above code. Will both the above specs pass?</p>
-    <answer>Yes</answer>
-    <answer correct>No</answer>
-    <explanation>Remember that any state created with `let` will reset for each new `it` block. Resetting the state before each individual test can help make the test code easier to understand and use. If you needed to get around this limitation, however, you could replace the `let` with a `before(:all)` / `before(:context)`, which would run only once: `before(:all) {@dog = Dog.new("Bear")}`. (You would need to change the variables in the tests to `@dog` as well.)</explanation>
-  </question>
-</quiz>
\ No newline at end of file
+#### Consider the above code. Will both the above specs pass?</p>
+- [ ] Yes
+- [ ] No
+
+<details><summary>Answer:</summary>
+
+- No</details>
+<details><summary>Explanation:</summary>
+
+Remember that any state created with `let` will reset for each new `it` block. Resetting the state before each individual test can help make the test code easier to understand and use. If you needed to get around this limitation, however, you could replace the `let` with a `before(:all)` / `before(:context)`, which would run only once: `before(:all) {@dog = Dog.new("Bear")}`. (You would need to change the variables in the tests to `@dog` as well.)</details>
\ No newline at end of file
diff --git a/ruby/quizzes_originals/big_o.md b/ruby/quizzes_originals/big_o.md
new file mode 100644
index 0000000..9fd05c5
--- /dev/null
+++ b/ruby/quizzes_originals/big_o.md
@@ -0,0 +1,85 @@
+# Big-O Quiz
+
+<quiz>
+  <question>
+    <p>Which of the following represents an ordering of strictly increasing time complexity?</p>
+    <answer>`O(n log n)` < `O(log n)` < `O(n)` < `O(n^2)` < `O(n!)` < `O(2^n)`</answer>
+    <answer correct>`O(1)` < `O(log n)` < `O(n)` < `O(n log n)` < `O(n^2)` < `O(2^n)` < `O(n!)`</answer>
+    <answer>`O(n^3)` < `O(n^2)` < `O(2^n)` < `O(n log n)` < `O(n)` < `O(log n)` < `O(1)`</answer>
+    <answer>`O(n)` < `O(2n)` < `O(3n)` < `O(n + 1)` < `O(n + 2)` < `O(n + 3)`</answer>
+    <answer>`O(1)` < `O(log n)` < `O(n)` < `O(n^2)` < `O(n!)` < `O(2^n)` < `O(n^n)`</answer>
+    <explanation>Remember `O(1)`, or constant time, is the slowest growing in terms of time complexity and  `O(n!)`, or factorial time, is the fastest growing.</explanation>
+  </question>
+</quiz>
+
+
+<quiz>
+  <question>
+    <p>What is the asymptotic representation of the following time complexity: `O(2n^3 + .5n^2 + 1000n)`</p>
+    <answer>`O(2n^3)`</answer>
+    <answer>`O(n^3 + n^2 + n)`</answer>
+    <answer>`O(1000n)`</answer>
+    <answer correct>`O(n^3)`</answer>
+    <answer>`O(2n^3 + .5n^2 + 1000n)`</answer>
+    <answer>`O(.5n^2)`</answer>
+    <explanation>Ignoring the constants, we get `n^3 + n^2 + n`.  `n^3` will dominate the other terms and therefore is the asymptotic representation.</explanation>
+  </question>
+</quiz>
+
+
+<quiz>
+  <question>
+    <p>Which of the following time complexities is linearithmic?</p>
+    <answer>`O(n^2)`</answer>
+    <answer>`O(n!)`</answer>
+    <answer>`O(2^n)`</answer>
+    <answer correct>`O(n log n)`</answer>
+    <answer>`O(n)`</answer>
+    <explanation>Remember linearithmic, or loglinear, time is `O(n log n)`. This is also the time complexity for `merge sort`, which is one of the fastest comparison sorts. </explanation>
+  </question>
+</quiz>
+
+
+```ruby
+  def max_squared_value(arr)
+    max = nil
+
+    arr.each do |num1|
+      is_max = true
+
+      arr.each do |num2|
+        is_max = false if num2 ** 2 > num1 ** 2
+      end
+
+      max = num1 if is_max
+    end
+
+    max
+  end
+```
+
+<quiz>
+  <question>
+    <p>What is the time complexity of the above function?</p>
+    <answer>`O(n log n)`</answer>
+    <answer correct>`O(n^2)`</answer>
+    <answer>`O(n)`</answer>
+    <answer>`O(n!)`</answer>
+    <answer>`O(1)`</answer>
+    <explanation>We are iterating over the input array of `n` elements. For each of those `n` elements, we do work that involves another iteration over the entire input array. In other words, for each of the `n` elements, we do `n` amount of work, which gives us `O(n^2)`.</explanation>
+  </question>
+</quiz>
+
+
+
+<quiz>
+  <question>
+    <p>What is the time complexity of ruby's `Array#permutation` method? **Note:** you do not need to look at the Ruby source code to answer this question.  Remember that Big-O notation is concerned with how runtime grows relative to the size of the input!</p>
+    <answer>`O(n*log(n))`</answer>
+    <answer>`O(n^2)`</answer>
+    <answer>`O(n)`</answer>
+    <answer correct>`O(n!)`</answer>
+    <answer>`O(1)`</answer>
+    <explanation>Whenever you have a problem where you are creating permutations, you are dealing with `factorial` time complexity. E.g., if you call the `Array#permutation` method of an array with the length of 3, then 3! permutations would be returned (6 permutations total). Increasing the length to 4 would then return 24 total permutations, or 4!.</explanation>
+  </question>
+</quiz>
\ No newline at end of file
diff --git a/ruby/quizzes_originals/data_structures.md b/ruby/quizzes_originals/data_structures.md
new file mode 100644
index 0000000..6912e95
--- /dev/null
+++ b/ruby/quizzes_originals/data_structures.md
@@ -0,0 +1,90 @@
+# Data Structures Quiz
+
+<quiz>
+  <question>
+    <p>LIFO (last-in-first-out) describes the behavior of which of the following?</p>
+    <answer>Queue</answer>
+    <answer>Set</answer>
+    <answer correct>Stack</answer>
+    <answer>Map</answer>
+    <explanation>When you stack things on top of each other, you have to remove the item off the top first. We can remove the item at the bottom until all of the other items on top of it have been removed.  So the first thing that goes in is actually the last thing that comes out.</explanation>
+  </question>
+</quiz>
+
+
+```ruby
+        N
+        / \
+      N   N
+      / \   
+    N   N
+    /
+  N
+```
+
+<quiz>
+  <question>
+    <p>Is the above graph a binary tree?</p>
+    <answer>No</answer>
+    <answer correct>Yes</answer>
+    <explanation>A binary tree is a graph with the constrant that a node can have at most two children.</explanation>
+  </question>
+</quiz>
+
+
+<quiz>
+  <question>
+    <p>BFS (breadth first search) uses which of the following ADTs?</p>
+    <answer correct>Queue</answer>
+    <answer>Set</answer>
+    <answer>Stack</answer>
+    <answer>Map</answer>
+    <explanation>As we are looking at each node, we want to add their children to our list of nodes to look at.  A queue allows us to utilize FIFO (first in first out) so that the order in which the nodes are added to our list is the order in which they will be dealt with.</explanation>
+  </question>
+</quiz>
+
+
+```ruby
+        1   
+        / \
+      2   5
+      /   / \
+    3   6   9
+    /   / \
+  4   7   8
+```
+
+<quiz>
+  <question>
+    <p>If we used DFS to try and find the node with value 6 in the graph above, what is a possible ordering of nodes that would be visited?</p>
+    <answer>1-2-5-3-6</answer>
+    <answer correct>1-2-3-4-5-6</answer>
+    <answer>4-3-2-1-7-8-6</answer>
+    <answer>8-7-4-9-6</answer>
+    <explanation>For DFS, we will look at a node, and then look at it's first child, and then that nodes first child and so on until we hit a leaf node or find the node we are searching for.  When we hit a leaf node, we will begin popping off the stack of recursive calls (going back up the tree a level at a time) and looking at the next child for that node. Once we find the node we are looking for, we start popping off the stack of recursive calls returning the node we found that has the value we are looking for.</explanation>
+  </question>
+</quiz>
+
+
+```ruby
+        D   
+        / \
+      A   E
+      / \   \
+    I   C   G
+    / \     /
+  H   F   B
+```
+
+<quiz>
+  <question>
+    <p>Which node in the above graph is the root?</p>
+    <answer>`A`</answer>
+    <answer>`B`</answer>
+    <answer correct>`D`</answer>
+    <answer>`F`</answer>
+    <answer>`H`</answer>
+    <answer>`I`</answer>
+    <explanation>The root node refers to the top most node that has no parent node.</explanation>
+  </question>
+</quiz>
diff --git a/ruby/quizzes_originals/git.md b/ruby/quizzes_originals/git.md
new file mode 100644
index 0000000..4794788
--- /dev/null
+++ b/ruby/quizzes_originals/git.md
@@ -0,0 +1,47 @@
+# Git Quiz
+
+<quiz>
+  <question>
+    <p>I want to push changes in my workspace to a remote repository. Which of the following outlines the correct workflow for pushing local changes to a remote repo?</p>
+    <answer correct>workspace -> index (staging area) -> local repository -> upstream repository</answer>
+    <answer>workspace -> local repository -> index (staging area) -> upstream repository</answer>
+    <answer>local repository -> workspace -> index (staging area) -> upstream repository</answer>
+    <explanation>We make changes to our local workspace, then we need to stage the changes so that they can be commited to our local repository (the hidden .git directory in our workspace) and then we can push them to the upstream remote repository.</explanation>
+  </question>
+</quiz>
+
+
+<quiz>
+  <question>
+    <p>How would you create a new branch and switch to it at the same time?</p>
+    <answer>`git -b checkout`</answer>
+    <answer>`git branch`</answer>
+    <answer correct>`git checkout -b`</answer>
+    <answer>`git branch -co`</answer>
+    <explanation>`git checkout -b` will do both for us! Instead of having to run `git branch <branch-name>` and then `git checkout <branch-name>`</explanation>
+  </question>
+</quiz>
+
+
+<quiz>
+  <question>
+    <p>Oh no! We've messed up and coded unwanted changes to our local project! How can we go back to a previous commit and get rid of the unwanted changes?</p>
+    <answer>`git rollback --soft`</answer>
+    <answer>`git undo HEAD`</answer>
+    <answer correct>`git reset --hard`</answer>
+    <answer>`git revert HEAD`</answer>
+    <explanation>`git reset --hard` will will wipe out all tracked changes back to the most recent commit.</explanation>
+  </question>
+</quiz>
+
+
+<quiz>
+  <question>
+    <p>Our remote and local repositories have gotten so out of alignment that we just want to ignore any conflicts and push our local code up to remote. How would we do this?</p>
+    <answer correct>`git push -f`</answer>
+    <answer>`git push`</answer>
+    <answer>`git force push`</answer>
+    <answer>`git push -u`</answer>
+    <explanation>The `-f` flag is short for `--force` which overrides any conflicts our local repo has with the remote repo.</explanation>
+  </question>
+</quiz>
\ No newline at end of file
diff --git a/ruby/quizzes_originals/lru_cache.md b/ruby/quizzes_originals/lru_cache.md
new file mode 100644
index 0000000..4162491
--- /dev/null
+++ b/ruby/quizzes_originals/lru_cache.md
@@ -0,0 +1,55 @@
+# LRU Cache Quiz
+
+```ruby
+  class Fixnum
+    def my_hashing_function
+      self * rand(10_000_000)
+    end
+  end
+```
+
+<quiz>
+  <question>
+    <p>Is the above function a hashing function?</p>
+    <answer>Yes</answer>
+    <answer correct>No</answer>
+    <explanation>A hashing function must be **deterministic**: the same input should always produce the same output, which won't happen if the output relies on a randomly generated number!</explanation>
+  </question>
+</quiz>
+
+
+<quiz>
+  <question>
+    <p>In a linked list, what is the time complexity for accessing the nth element?</p>
+    <answer>`O(1)`</answer>
+    <answer>`O(log n)`</answer>
+    <answer correct>`O(n)`</answer>
+    <answer>`O(n log n)`</answer>
+    <answer>`O(n^2)`</answer>
+    <explanation>Unlike with an array or hash--which allow access to the nth element by index and key, respectively--accessing the nth element in a linked list requires following links from the first element to each successive element until reaching the nth one, an `O(n)` operation.</explanation>
+  </question>
+</quiz>
+
+```ruby
+  {4,78,12,56,44,78,15}
+```
+
+<quiz>
+  <question>
+    <p>Is the above a set?</p>
+    <answer>Yes</answer>
+    <answer correct>No</answer>
+    <explanation>A set is a data type that stores *unique* items.</explanation>
+  </question>
+</quiz>
+
+<quiz>
+  <question multiple>
+    <p>An array is an example of which of the following? (Select all that apply.)</p>
+    <answer>Abstract Data Type</answer>
+    <answer>Algorithm</answer>
+    <answer correct>Data Structure</answer>
+    <answer>Transfer Function</answer>
+    <explanation>An array is an example of a data structure! :)</explanation>
+  </question>
+</quiz>
diff --git a/ruby/quizzes_originals/oop_1.md b/ruby/quizzes_originals/oop_1.md
new file mode 100644
index 0000000..29bbb35
--- /dev/null
+++ b/ruby/quizzes_originals/oop_1.md
@@ -0,0 +1,127 @@
+# OOP Quiz 1
+
+```ruby
+  class Dance
+    attr_reader :style
+
+    def initialize(style = "Tap")
+      @style = style
+    end
+  end
+
+  class Ballet < Dance
+    def initialize(technique)
+      @technique = technique
+      super("Ballet")
+    end
+  end
+
+  class Swing < Dance
+    def initialize(form)
+      @form = form
+      super
+    end
+  end
+
+  bolshoi = Ballet.new("Vaganova")
+  west_coast_swing = Swing.new("West Coast")
+```
+
+<quiz>
+  <question>
+    <p>Consider the above code. What are the respective return values from calling `bolshoi.style` and `west_coast_swing.style`?</p>
+    <answer>`"Tap"`, `"Tap"`</answer>
+    <answer>`"Ballet"`, `"Tap"`</answer>
+    <answer correct>`"Ballet"`, `"West Coast"`</answer>
+    <answer>`"Vaganova"`, `"Ballet"`</answer>
+    <answer>`"Vaganova"`, `"West Coast"`</answer>
+    <explanation>When called without any arguments (as in `Swing#initialize`), the `super` keyword will take all the arguments passed in to the current method and pass them as arguments to the parent class's version of the method. So `west_coast_swing` will have its `@style` set to "West Coast", i.e., the argument originally passed in to `Swing#initialize`. The `Ballet` class, however, does specify an argument for `super` to pass to its parent `Dance` class: "Ballet". `bolshoi`'s `@style` will accordingly be set to "Ballet". </explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+  class EngineStalledError < StandardError
+  end
+
+  class CollisionOccurredError < StandardError
+  end
+
+  def drive_car
+    # engine may stall, collision may occur
+  end
+
+  begin
+    drive_car
+  rescue EngineStalledError => e
+    puts "Rescued from engine stalled!"
+    retry
+  rescue CollisionOccurredError => e
+    puts "Rescued from collision!"
+  ensure
+    puts "Car stopped."
+  end
+```
+
+<quiz>
+  <question>
+    <p>Consider the above example. The first time `drive_car` is called, an EngineStalledError is raised! What happens next?</p>
+    <answer>The program outputs `"Rescued from engine stalled!"` then `"Car stopped."`</answer>
+    <answer>An uncaught error is thrown</answer>
+    <answer correct>The program outputs `"Rescued from engine stalled!"` then retries running the code block </answer>
+    <answer>The program outputs `"Car stopped."`</answer>
+    <explanation>After rescuing the `EngineStalledError` this code block will hit the `retry` keyword.</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+  class BoxOffice
+    def initialize(num_seats, show_title)
+      @num_seats = num_seats
+      @show_title = show_title
+      @tickets_sold = 0
+    end
+
+    def sell_ticket
+      # logic for the ticket selling process goes here
+
+      update_tickets_sold
+    end
+
+    private
+
+    def update_tickets_sold
+      @tickets_sold += 1
+    end
+  end
+
+  tkts = BoxOffice.new(2000, "Rent")
+```
+
+<quiz>
+  <question>
+    <p>Consider the above code. Which of the following is a valid way to increase the number of `tkts` tickets sold by 1?</p>
+    <answer>`tkts.update_tickets_sold`</answer>
+    <answer>`BoxOffice.update_tickets_sold`</answer>
+    <answer correct>`tkts.sell_ticket`</answer>
+    <answer>`tkts.tickets_sold += 1`</answer>
+    <answer>`BoxOffice.sell_ticket`</answer>
+    <explanation>To increase the number of tickets sold for the `tkts` instance of the `BoxOffice` class, you just need to call the `sell_ticket` method on that instance.</explanation>
+  </question>
+</quiz>
+
+
+<quiz>
+  <question>
+    <p>You are writing a program that makes sandwiches. Each sandwich has a protein, a condiment, and two slices of bread. There are different types of proteins, condiments, and breads, but within each of those categories, the different types are functionally all the same. According to the principles of Object-Oriented Programming, what classes should you create for your program?</p>
+    <answer>Sandwich, Bread, RyeBread, SourDoughBread, WholeWheatBread, Protein, 
+    Chicken, Tofu, Seitan, Turkey, Condiment, Mustard, Ketchup, Mayo</answer>
+    <answer correct>Sandwich, Bread, Protein, Condiment</answer>
+    <answer>Sandwich</answer>
+    <answer>Sandwich, Bread, Protein, Mustard, Ketchup, Aioli</answer>
+    <explanation>When taking an OOP approach, you typically want to break your program down into base classes (like `Bread`) that have a single responsibility / reason to change. If Sandwich were the only class, it would have to change whenever you needed to update the functionality of proteins, condiments, or bread, thus violating the preceding principle. At the same time, you don't need to break proteins, condiments, and bread down further because all of their different types share the same functionality.</explanation>
+  </question>
+</quiz>
\ No newline at end of file
diff --git a/ruby/quizzes_originals/oop_2.md b/ruby/quizzes_originals/oop_2.md
new file mode 100644
index 0000000..79fee69
--- /dev/null
+++ b/ruby/quizzes_originals/oop_2.md
@@ -0,0 +1,136 @@
+# OOP Quiz 2
+
+```ruby
+  class Municipality
+    attr_reader :state
+
+    def initialize(state = "California")
+      @state = state
+    end
+  end
+
+  class City < Municipality
+    def initialize(name, state)
+      @name = name
+      super(state)
+    end
+  end
+
+  class Town < Municipality
+    def initialize(population)
+      @population = population
+      super
+    end
+  end
+
+  class County < Municipality
+    def change_state(new_state)
+      self.state = new_state
+    end
+  end
+
+  nyc = City.new("New York City", "New York")
+  oaktown = Town.new(500000)
+  marin = County.new
+```
+
+<quiz>
+  <question>
+    <p>Consider the above code. What are the respective return values from calling `nyc.state`, `oaktown.state`, and `marin.state`?</p>
+    <answer>`"New York"`, `"California"`, `"California"`</answer>
+    <answer>`"New York City"`, `"California"`, `"Marin"`</answer>
+    <answer correct>`"New York"`, `500000`, `"California"`</answer>
+    <answer>`"New York City"`, `"California"`, `NoMethodError`</answer>
+    <answer>`"California"`, `"California"`, `"California"`</answer>
+    <explanation>`City#initialize` explicitly passes its `state` parameter (here, `"New York"`) to `super`. `Town#initialize`, in contrast, just calls `super`, which passes along all of `Town#initialize`'s incoming arguments (here, `500000`) to `Municipality#initialize`. (To avoid passing along its arguments and have `super` apply the default argument of `"California"`, `Town#initialize` would need to indicate explicitly that it was calling `super` without any arguments, i.e., `super()`.) Finally, since the `County` class does not have a defined initialize method, calling `new`  on `County` will run the parent class's `initialize` method, thereby setting `state` to the default value of `"California"`. 
+    </explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+class Board
+  def initialize
+    @grid = Array.new(8) { Array.new(8) { NullPiece.instance }}
+  end
+
+  def [](pos)
+    row, col = pos
+    @grid[row][col]
+  end
+
+  def []=(pos, val)
+    row, col = pos
+    @grid[row][col] = val
+  end
+
+  def add_piece(pos, piece)
+    @grid[pos] = piece
+  end
+end
+
+board = Board.new
+board.add_piece([0,0], Pawn.new)
+```
+
+<quiz>
+  <question>
+    <p>Why will the code above not add the pawn to `0, 0` as expected?</p>
+    <answer>The `*` splat operator should be used in `#add_piece` when indexing into the grid: `@grid[*pos] = piece`</answer>
+    <answer correct>`#add_piece` should call `self[pos]` rather than `@grid[pos]`</answer>
+    <answer>There should be an `attr_reader` for the `@grid` instance variable.</answer>
+    <answer>Nothing is wrong with the above code.</answer>
+    <explanation>It will not add the pawn because `@grid[pos]` in `#add_piece` resolves to `@grid[[0,0]]`, which will produce `TypeError: no implicit conversion of Array into Integer`. It produces this error because `@grid` is an `Array`, and the `Array#[]` method expects an integer as an argument, not an array (i.e., not `[0,0]`). To avoid this problem, note that the `Board#[]` and `Board#[]=` methods both expect an array as an argument (`pos`) and use that array to access `@grid` for you. `#add_piece` will accordingly add the pawn successfully if it instead calls `self[pos] = piece`.</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+class Pawn
+  attr_accessor :position
+  
+  def initialize(position)
+    @position = position
+  end
+end
+
+pawn = Pawn.new([0, 1])
+pawn_copy = pawn.dup
+
+pawn_copy.position[1] = "CHANGED"
+pawn.position
+```
+
+<quiz>
+  <question>
+    <p>Consider the above code, which uses Ruby's native `#dup` method. What will `pawn` and `pawn_copy`'s positions be? </p>
+    <answer correct>`[0, "CHANGED"]`, `[0, "CHANGED"]`</answer>
+    <answer>`[0, 1]`, `[0, "CHANGED"]`</answer>
+    <answer>`[0, 1]`, `[0, 1]`</answer>
+    <answer>`[0, "CHANGED"]`, `[0, 1]`</answer>
+    <explanation>Remember that Ruby's native `#dup` method only makes a shallow copy. This means that it copies the references stored in instance variables instead of creating new copies of the objects they reference. `pawn` and `pawn_copy` will accordingly both reference the same array, but if they both reference the same array, then changing that array in one instance will also change it in the other! To avoid this problem, you would need to create a new position array when making your second pawn.</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+class Piece
+  include Singleton
+  # ...
+
+end
+```
+
+<quiz>
+  <question>
+    <p>Consider the above code. How would you create and refer to this `Piece` object?</p>
+    <answer>`Piece.new`</answer>
+    <answer>`Piece.create`</answer>
+    <answer correct>`Piece.instance`</answer>
+    <answer>`Singleton.instance`</answer>
+    <explanation>The `Singleton` module allows you to have only one instance of a class. You would invoke that singular instance using `Piece.instance`. </explanation>
+  </question>
+</quiz>
\ No newline at end of file
diff --git a/ruby/quizzes_originals/recursion.md b/ruby/quizzes_originals/recursion.md
new file mode 100644
index 0000000..6181d7b
--- /dev/null
+++ b/ruby/quizzes_originals/recursion.md
@@ -0,0 +1,93 @@
+# Recursion Quiz
+
+```ruby
+  def func(arg1, arg2)
+    temp = arg1 * arg2
+    return_val = (temp ** 2) + (arg1 % 6 + 1) / (7 + arg2 + arg1)
+  end
+```
+
+<quiz>
+  <question multiple>
+    <p>What is wrong with the above function?</p>
+    <answer>Indentation is wrong</answer>
+    <answer correct>Variable names are not descriptive</answer>
+    <answer correct>Code needs to be broken out over more lines</answer>
+    <answer>This code cannot be improved</answer>
+    <explanation>`arg1` and `arg2` don't give us any idea about what the numbers should be representing that will be passed in. Additionally, the math for `return_val` is not intuitive and should be broken up.</explanation>
+  </question>
+</quiz>
+
+
+<quiz>
+  <question multiple>
+    <p>Suppose we have a function called `args_matey` which expects 3 arguments: a string, an array, and a hash. Select each of the following that correctly passes these arguments:</p>
+    <answer correct>`args_matey('argument 1', [1,2,3,4], hash: 'is', last: 'argument')`</answer>
+    <answer correct>`args_matey('argument 1', [1,2,3,4], { hash: 'is', last: 'argument' })`</answer>
+    <explanation>As long as the hash is the last argument given in the method invocation, ruby will assume that the key value pairs are part of the expected hash. So, we don't have to include the curly braces in this scenario.</explanation>
+  </question>
+</quiz>
+
+
+```ruby
+  def add_odds(n)
+    return n if n == 1
+
+    if n.even?
+      add_odds(n-1)
+    else
+      n + add_odds(n-1)
+    end
+  end
+```
+
+<quiz>
+  <question multiple>
+    <p>Consider the above function that calculates the sum of all odd integers from 1 to n (inclusive). For which of the following test cases will the above function throw a stack overflow error?</p>
+    <answer>`add_odds(9)`</answer>
+    <answer correct>`add_odds(50000)`</answer>
+    <answer>`add_odds(123)`</answer>
+    <answer correct>`add_odds(-8)`</answer>
+    <answer>`add_odds(1)`</answer>
+    <explanation>The average computer setup will give us around 9000 stack frames before throwing a stack overflow error. With an input of 50000, our method would try to create 50000 stacks and would get cut off before it gets there. with an input of -8, our function will continue to make recursive calls and add stack frames indefinitely because we will never hit our base case which checks that `n` is equal to 1. `n` will never be equal to 1.</explanation>
+  </question>
+</quiz>
+
+
+```ruby
+  class Array
+    def upcase
+      self.map { |string| string.upcase }
+    end
+  end
+```
+
+<quiz>
+  <question>
+    <p>Consider the above function, which is defined for a 1-D array of strings. This function is:</p>
+    <answer>Recursive</answer>
+    <answer correct>Iterative</answer>
+    <explanation>Each element in our array is an instance of a String. When we invoke `string.upcase` we are invoking the upcase method that is written on the String class. The `upcase` method above is written on the Array class. Therefore, we are not calling the same method inside of the `map` iteration.</explanation>
+  </question>
+</quiz>
+
+
+```ruby
+  def powers_sum(n)
+    return n if n == 1
+
+    (n * n) * powers_sum(n-1)
+  end
+```
+
+<quiz>
+  <question>
+    <p>Consider the above function. How many stack frames are produced from calling `powers_sum(n)`? (assume n > 0)</p>
+    <answer correct>`n`</answer>
+    <answer>`n+1`</answer>
+    <answer>`2n`</answer>
+    <answer>`n^2`</answer>
+    <answer>`cannot be determined`</answer>
+    <explanation>For each recursive call, we open up one additional stack frame because we invoke `powers_sum` once for each call. We decrease our number, `n`, by 1 for each call. Therefore there will be `n` stack frames.</explanation>
+  </question>
+</quiz>
diff --git a/ruby/quizzes_originals/reference.md b/ruby/quizzes_originals/reference.md
new file mode 100644
index 0000000..bcc0e03
--- /dev/null
+++ b/ruby/quizzes_originals/reference.md
@@ -0,0 +1,105 @@
+# Reference Quiz
+
+```ruby
+  arr = Array.new(3, [])
+  arr[0] << "Foo"
+  arr
+```
+<quiz>
+  <question>
+    <p>What will be the output of the above code?</p>
+    <answer correct>`[["Foo"] ,["Foo"], ["Foo"]]`</answer>
+    <answer>`[[], [], []]`</answer>
+    <answer>`[["Foo"], [], []]`</answer>
+    <answer>`["Foo", [], []]`</answer>
+    <answer>`["Foo", "Foo", "Foo"]`</answer>
+    <answer>None of the above</answer>
+    <explanation>The three empty arrays in `arr` are all the same array in memory (same object id).  When we shovel something into the first array, all three get modified because each element in our parent array has a memory pointer to the same array.</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+  arr = Array.new(3) { [] }
+  arr[0] << "Foo"
+  arr
+```
+
+<quiz>
+  <question>
+    <p>What will be the output of the above code?</p>
+    <answer>`[[], [], []]`</answer>
+    <answer correct>`[["Foo"], [], []]`</answer>
+    <answer>`["Foo", [], []]`</answer>
+    <answer>`["Foo", "Foo", "Foo"]`</answer>
+    <answer>`[["Foo"] ,["Foo"], ["Foo"]]`</answer>
+    <answer>None of the above</answer>
+    <explanation>Passing a block to `Array.new` creates a new array with a different object id for every element in `arr`.</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+  x = 15
+  def foo(x)
+    x = 10
+  end
+  foo(x)
+  p x
+```
+
+<quiz>
+  <question>
+    <p>What will be the output of the above code?</p>
+    <answer>`42`</answer>
+    <answer correct>`15`</answer>
+    <answer>`"x"`</answer>
+    <answer>`10`</answer>
+    <answer>`nil`</answer>
+    <answer>None of the above</answer>
+    <explanation>When printing `x`, ruby will check the current scope for a variable named `x`.  In this case, x is set to 15.  When you define a function `def` you are creating a new scope that is fully contained by the method definition.  Ruby will not look into that scope for a variable named `x`.</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+  x = []
+  def foo(x)
+    x << "Fancy Feast"
+  end
+  foo(x)
+  p x
+```
+
+<quiz>
+  <question>
+    <p>What will be the output of the above code?</p>
+    <answer correct>`["Fancy Feast"]`</answer>
+    <answer>`"Fancy Feast"`</answer>
+    <answer>`[]`</answer>
+    <answer>`nil`</answer>
+    <answer>`["Fancy", "Feast"]`</answer>
+    <answer>None of the above</answer>
+    <explanation>Since we are passing the array, `x`, into the invocation of `foo`, the local variable `x` inside the scope of the `foo` method has a pointer to the same array in the outter scope.</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+  game.board[pos].revealed = true if !guess && game.board[pos] && game.board[pos].revealed == false
+```
+
+<quiz>
+  <question multiple>
+    <p>What's wrong with the above line of code?</p>
+    <answer correct>Long method chain suggests Law of Demeter violation</answer>
+    <answer correct>`if !condition` is not stylistic ruby</answer>
+    <answer correct>Objects are tightly coupled</answer>
+    <answer correct>Code is not DRY</answer>
+    <explanation>We are chaining too many methods.  The `!if` should be changed to `unless` when possible. We are relying on the `board` information on the `game` for every call instead of being able to call a method directly on the game. And the `game.board[pos]` is repeated many times making it complicated to understand right off the bat.</explanation>
+  </question>
+</quiz>
diff --git a/ruby/quizzes_originals/rspec_tdd.md b/ruby/quizzes_originals/rspec_tdd.md
new file mode 100644
index 0000000..8f859e8
--- /dev/null
+++ b/ruby/quizzes_originals/rspec_tdd.md
@@ -0,0 +1,136 @@
+# RSpec and TDD Quiz
+
+```ruby
+# Directory Structure:
+
+  # my_cool_project
+  #   lib/
+  #     hello_world.rb
+  #   hello_world_spec.rb
+
+# Spec File:
+
+  # hello_world_spec.rb
+
+  require 'rspec'
+  require 'hello_world'
+
+  describe '#hello_world' do
+
+  end
+```
+
+<quiz>
+  <question>
+    <p>What is wrong with the above setup for testing with RSpec?</p>
+    <answer>Spec file should say `require_relative './lib/hello_world'` instead of `require 'hello_world'`.</answer>
+    <answer correct>`hello_world_spec.rb` should live in a `spec` directory adjacent to the `lib` directory.</answer>
+    <answer>`hello_world_spec` should be a `.rspec` file instead of `.rb`.</answer>
+    <explanation>Your spec files should live in a `spec` directory adjacent to your `lib` directory that contains what is being tested.</explanation>
+  </question>
+</quiz>
+
+
+```ruby
+  describe '#hello' do
+    context 'with an odd number' do
+      expect(hello(5)).to eq('hi')
+    end
+  end
+```
+
+<quiz>
+  <question>
+    <p>What is wrong with the above spec's syntax?</p>
+    <answer correct>An `expect` statement must be nested within an `it` block.</answer>
+    <answer>A `context` block cannot be nested within a `describe` block.</answer>
+    <answer>`to eq('hi')` should read `to_eq('hi')`.</answer>
+    <answer>Nothing is wrong with the spec's syntax.</answer>
+    <explanation>Remember that RSpec proper syntax!</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+  describe Robot do
+    describe '#valid_walk?' do
+      context 'when valid' do
+        it 'should return true' do
+          robot = Robot.new
+          expect(robot.valid_walk?("NS")).to be true
+        end
+      end
+    end
+  end
+```
+
+<quiz>
+  <question>
+    <p>What is wrong with the above spec's syntax?</p>
+    <answer>`Robot` should be a string.</answer>
+    <answer>A `describe` block cannot be nested within a `describe` block.</answer>
+    <answer>`to be true` should be `to_be true`.</answer>
+    <answer correct>Nothing is wrong with the spec's syntax.</answer>
+    <explanation>This spec looks good!</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+describe '#error_raiser' do
+  it 'has a pending spec'
+
+  it 'should raise an error' do
+    expect(error_raiser('raise')).to raise_error(ArgumentError)
+  end
+end
+```
+
+<quiz>
+  <question>
+    <p>What is wrong with the above spec's syntax?</p>
+    <answer>The pending spec is invalid.</answer>
+    <answer correct>`expect(error_raiser('raise'))` should be `expect {error_raiser('raise')}`.</answer>
+    <answer>`ArgumentError` should be a string.</answer>
+    <answer>Nothing is wrong with the spec's syntax.</answer>
+    <explanation>Remember to wrap any spec expected to raise an error in curly braces. This will effectively create a `begin` & `rescue` block for you.</explanation>
+  </question>
+</quiz>
+
+
+
+```ruby
+class Dog
+  attr_accessor :name
+
+  def initialize(name)
+    @name = name
+  end
+end
+
+describe Dog do
+  let(:dog) { Dog.new("Bear") }
+
+  describe "name property" do
+    it "allows us to manipulate name" do
+      dog.name = "Rocky"
+      expect(dog.name).to eq("Rocky")
+    end
+
+    it "allows us to read the name" do
+      expect(dog.name).to eq("Rocky")
+    end
+  end
+end
+```
+
+<quiz>
+  <question>
+    <p>Consider the above code. Will both the above specs pass?</p>
+    <answer>Yes</answer>
+    <answer correct>No</answer>
+    <explanation>Remember that any state created with `let` will reset for each new `it` block. Resetting the state before each individual test can help make the test code easier to understand and use. If you needed to get around this limitation, however, you could replace the `let` with a `before(:all)` / `before(:context)`, which would run only once: `before(:all) {@dog = Dog.new("Bear")}`. (You would need to change the variables in the tests to `@dog` as well.)</explanation>
+  </question>
+</quiz>
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