Merge pull request #2207 from wiremock/comaintainers

Add WireMock co-maintainers role and document the merge process

CONTRIBUTING.md

@@ -106,3 +106,45 @@ The website sources are located here: [wiremock/wiremock.org](https://github.com
 All the documentation is located under the `_docs` directory as Markdown files,
 and it can be edited with all modern text editors and IDEs.
 See the repository's contributor guide for more information.
+
+## Merge process
+
+Merges to this repository can be performed by the WireMock maintainer ([Tom Akehurst](https://github.com/tomakehurst))
+and by _co-maintainers_ assigned by him.
+This is a [community role](https://github.com/wiremock/community/blob/main/governance/README.md)
+designed for WireMock itself and other key repositories,
+specifically to facilitate review and changes while WireMock 3 is in beta
+and receives a lot of incremental patches.
+
+- The maintainers are responsible to verify the pull request readiness
+  in accordance with contributing guidelines (e.g. code quality, test automation, documentation, etc.).
+  The pull request can only be approved if these requirements are met
+- In the beginning, a review by one co-maintainer is required for the merge,
+  unless there are negative reviews and unaddressed comments by other contributors
+- After the approval, it is generally recommended to give at least 24 hours for reviews before merging
+
+Beyond WireMock 3.x Beta releases, the scope of responsibilities for co-maintainers
+is yet to be determined based on the experiences with this role for the Beta versions.
+
+### What can be merged by co-maintainers
+
+While WireMock 3.x is in Beta, co-maintainers can merge the following pull requests:
+
+- Minor features and improvements that do not impact the WireMock architecture
+- Refactorings, including the major ones, e.g. Guava replacement
+- Test Automation
+- Non-production repository changes: documentation (including Javadoc), GitHub Actions, bots and automation
+- Dependency updates for shaded dependencies, patch/minor versions for projects following the Semantic Versioning notation
+
+### What CANNOT be merged by co-maintainers without BDFL’s approval
+
+The following changes need a review by Tom Akehurst before being merged.
+
+- Any compatibility breaking changes, including binary API and REST API,
+  unless pre-approved by the BDFL in the associated GitHub issue
+- New request matchers (patterns)
+- Substantial changes to WireMock Architecture and API.
+  Examples: New REST API end-points, major features like GraphQL fetching
+- Inclusion of new libraries, even if shaded
+- Major version Dependency updates, e.g. Jetty 11 => 12
+- Changes in the deliverable artefacts, e.g. new modules