diff --git a/features/step_definitions/attachment_steps.rb b/features/step_definitions/attachment_steps.rb
index 5ad7ce2..1aecc3a 100644
--- a/features/step_definitions/attachment_steps.rb
+++ b/features/step_definitions/attachment_steps.rb
@@ -49,7 +49,13 @@ def attachment_path(filename)
 
 Then /^the attachment should have the same content type as the fixture "([^"]*)"$/ do |filename|
   in_current_dir do
-    require 'mime/types'
+    begin
+      # Use mime/types/columnar if available, for reduced memory usage
+      require "mime/types/columnar"
+    rescue LoadError
+      require "mime/types"
+    end
+
     attachment_content_type = `bundle exec #{runner_command} "puts User.last.attachment_content_type"`.strip
     attachment_content_type.should == MIME::Types.type_for(filename).first.content_type
   end
diff --git a/lib/paperclip.rb b/lib/paperclip.rb
index 6750224..c0e0733 100644
--- a/lib/paperclip.rb
+++ b/lib/paperclip.rb
@@ -56,7 +56,14 @@
 require 'paperclip/attachment_registry'
 require 'paperclip/filename_cleaner'
 require 'paperclip/rails_environment'
-require 'mime/types'
+
+begin
+  # Use mime/types/columnar if available, for reduced memory usage
+  require "mime/types/columnar"
+rescue LoadError
+  require "mime/types"
+end
+
 require 'mimemagic'
 require 'mimemagic/overlay'
 require 'logger'