diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index b359f9863..e15e04180 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -1,5 +1,6 @@
+repos:
 - repo: https://github.com/pre-commit/pre-commit-hooks
-  rev: v2.2.3
+  rev: v4.4.0
   hooks:
   - id: trailing-whitespace
     exclude: &exclude_files >
@@ -10,7 +11,7 @@
       )$
 
 - repo: https://github.com/Lucas-C/pre-commit-hooks
-  rev: v1.1.10
+  rev: v1.3.1
   hooks:
   - id: remove-tabs
     args: [ '--whitespaces-count', '2']
diff --git a/.words.lst b/.words.lst
index c6ab39a03..5325fe295 100644
--- a/.words.lst
+++ b/.words.lst
@@ -1,6 +1,8 @@
-personal_ws-1.1 en 163
+personal_ws-1.1 en 205
+ABNF
 ACM
 Aa
+Acta
 Ao
 BaCa
 BadLuck
@@ -12,9 +14,12 @@ CSV
 CaCO
 ClNa
 ClosingBrace
+CommonMark
 ConstantFirstComparison
+Cryst
 EREs
 Edsger
+EqualityOperator
 EscapedChar
 ExpressionClause
 ExpressionPhrase
@@ -36,12 +41,17 @@ NaO
 OpenAPI
 OpeningBrace
 OperatorComparison
+OrderedConstant
+OrderedValue
+POSCAR
 POSIX
 PredicateComparison
 PropertyFirstComparison
 PropertyZipAddon
 Punctuator
 RST
+RelativeComparisonOperator
+SPDX
 Schmit
 SetOpRhs
 SetZipOpRhs
@@ -52,10 +62,14 @@ UTC
 UUID
 UnescapedChar
 UnicodeHighChar
+UnorderedConstant
 Unversioned
 UppercaseLetter
+ValueEqRhs
 ValueList
+ValueListEntry
 ValueOpRhs
+ValueRelCompRhs
 ValueZip
 ValueZipList
 Za
@@ -65,28 +79,39 @@ alphanumerics
 annote
 antlr
 api
+atime
 backend
+backends
 bandgap
 bd
 booktitle
 boolean
 calc
 cartesian
+checksums
+cif
 conformant
 cr
 crossref
 css
 csv
+ctime
 deNOx
 dec
 denox
 dep
+dependentRequired
 dimensionality
 discoverability
 discoverable
 doi
 downloadable
+eb
 ebnf
+edf
+enum
+exclusiveMaximum
+exclusiveMinimum
 exmpl
 fieldname
 firstname
@@ -108,15 +133,25 @@ libc
 lst
 lt
 maintainer's
+maxItems
+maxLength
+maxProperties
+md
 metadata
+minItems
+minLength
+minProperties
 mistyped
+mtime
 multi
+multipleOf
 namespace
 namespaces
 nattached
 nbsp
 nelements
 nl
+nonperiodic
 nperiodic
 nsites
 occupancies
@@ -131,11 +166,13 @@ pre
 prepended
 prepending
 prev
+qudt
 queryable
 rc
 regex
 renormalize
 sectnum
+sha
 sortable
 spacegroup
 structs
@@ -146,10 +183,15 @@ supercell
 testdb
 timestamp
 timestamps
+ucum
+uniqueItems
 unrequested
 unversioned
+uri
+uris
 url
 urls
+uuid
 vMAJOR
 versioning
 vnd
diff --git a/AUTHORS b/AUTHORS
index 3ef04668e..54a6389ad 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -3,12 +3,15 @@ The OPTIMADE API has been developed with contributions by the participants of th
 - the CECAM in Lausanne, Switzerland from 2018-06-11 to 2018-06-15
 - the CECAM in Lausanne, Switzerland from 2019-06-11 to 2019-06-14
 - the CECAM in Lausanne, Switzerland (virtually) 2020-06-08 to 2020-06-12
+- the CECAM in Lausanne, Switzerland (virtually) 2021-06-07 to 2021-06-11
+- the CECAM in Lausanne, Switzerland 2022-05-30 to 2022-06-03
 
 Contributors to the development of the OPTIMADE specification and implementation in alphabetical order:
 Casper Andersen
 Thomas Archer
 Rickard Armiento
 Rossella Aversa
+Johan Bergsma
 Evgeny Blokhin
 Kamal Choudhary
 Pauline Colinet
@@ -57,6 +60,7 @@ Daniel Speckhard
 Leopold Talirz
 Cormac Toher
 Martin Uhrin
+Antanas Vaitkus
 Pierre Villars
 David Waroquiers
 Donald Winston
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 663a46072..ee4fda021 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,32 @@
 # Changelog
 
+## v1.2.0-rc.1 (December 2022)
+
+This is the first release candidate of v1.2.0 of the OPTIMADE API specification.
+It should contain all of the new features in the specification, but their implementation may be modified in the final release.
+
+Note: The OpenAPI schemas distributed in `./schemas` have not yet been modified with the new features 1.2.0.
+
+This minor release adds significant but optional new functionality to the specification, as well as providing several clarifications to existing behaviour.
+
+### New features
+
+- **Property definitions** ([#376](https://github.com/Materials-Consortia/OPTIMADE/pull/376)).
+A new section titled [Property Defintions](https://github.com/Materials-Consortia/OPTIMADE/blob/develop/optimade.rst#property-definitions) has been added to the specification which significantly extends the way in which implementations can define and describe the custom properties they serve, including URIs, unit definitions, API support levels (for querying and sorting) as well as full support for JSON Schema constructs for describing the JSON representation of the property.
+- **Files endpoint** ([#360](https://github.com/Materials-Consortia/OPTIMADE/pull/360)).
+The `/files` endpoint and corresponding [`files` entry
+type](https://github.com/Materials-Consortia/OPTIMADE/blob/develop/optimade.rst#files-entries) has been added to provide a robust way of linking entries to arbitrary file-based data relevant to the entry, such as alternative crystal structure representation formats, input or output files from computational procedures, or experimental data files.
+- **Boolean values** ([#348](https://github.com/Materials-Consortia/OPTIMADE/pull/348)).
+[Boolean values](https://github.com/Materials-Consortia/OPTIMADE/blob/develop/optimade.rst#comparisons-of-boolean-values) were overlooked in the first version of the filter grammar as no OPTIMADE fields required them.
+This functionality has been introduced for boolean fields using the syntax `TRUE` and `FALSE`.
+Only strict equality (`=`) and inequality (`!=`) comparisons on individual fields are supported.
+- **Fuzzy comparisons on lists** ([#415](https://github.com/Materials-Consortia/OPTIMADE/pull/415))
+String comparisons like `CONTAINS`, `STARTS WITH` and `ENDS WITH` are now compatible with list filter operations like `HAS`, `HAS ALL` etc.
+- **Backoff time** ([#411](https://github.com/Materials-Consortia/OPTIMADE/pull/411)):
+- **Database licenses** ([#414](https://github.com/Materials-Consortia/OPTIMADE/pull/414)):
+- **Symmetry data** ([#405](https://github.com/Materials-Consortia/OPTIMADE/pull/405)):
+
+
 ## v1.1.0 (July 8, 2021)
 
 This is release v1.1.0 of the OPTIMADE API specification.
diff --git a/README.md b/README.md
index 5f14ac8b6..cdb9be461 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,11 @@
-# OPTIMADE
+<div align="center" style="padding-bottom: 1em;">
+<img width="100px" align="center" src="https://matsci.org/uploads/default/original/2X/b/bd2f59b3bf14fb046b74538750699d7da4c19ac1.svg">
+</div>
+
+<h1 align="center">
+The OPTIMADE Specification
+</h1>
+
 
 The Open Databases Integration for Materials Design (OPTIMADE) consortium aims to make materials databases interoperational by developing a common REST API.
 
diff --git a/optimade.rst b/optimade.rst
index 09a0ccc9f..bd437f19b 100644
--- a/optimade.rst
+++ b/optimade.rst
@@ -1,6 +1,6 @@
-=========================================
-OPTIMADE API specification v1.1.0~develop
-=========================================
+======================================
+OPTIMADE API specification v1.2.0-rc.1
+======================================
 
 .. comment