The evolution of Cypher is driven by the production and acceptance of CIPs, which are written as a response to Cypher Improvement Requests (CIRs). CIRs are feature requests, and are raised as issues to the openCypher repository. CIPs are documents that outline the syntax and semantics of the proposed new Cypher features, and are raised as a PR to the openCypher repository.
CIPs that are accepted into the language exists at two integration levels and can be found in the openCypher repository's master branch in the respective directories:
Testable CIPs have test coverage in the TCK (Technology Compatibility Kit), while accpeted CIPs do not have such coverage. An accepted CIP can be promoted to a testable CIP by a PR to the openCypher repository that adds sufficient scenarios to the TCK.