1. Versioning
Rails follows a shifted version of semver:
Patch Z
Only bug fixes, no API changes, no new features. Except as necessary for security fixes.
Minor Y
New features, may contain API changes (Serve as major versions of Semver). Breaking changes are paired with deprecation notices in the previous minor or major release.
Major X
New features, will likely contain API changes. The difference between Rails' minor and major releases is the magnitude of breaking changes, and usually reserved for special occasions.
2. New Features
New features are only added to the main branch and will not be made available in Patch releases.
3. Bug Fixes
Minor releases will receive bug fixes for one year after the first release in its series. For example, if a theoretical 1.1.0 is released on January 1, 2023, it will receive bug fixes until January 1, 2024. After that, it will be considered unsupported.
Bug fixes are typically added to the main branch, and backported to the x-y-stable branch of the latest release series if there is sufficient need. When enough bugs fixes have been added to an x-y-stable branch, a new Patch release is built from it. For example, a theoretical 1.2.2 Patch release would be built from the 1-2-stable branch.
For unsupported series, bug fixes may coincidentally land in a stable branch, but won't be released in an official version. It is recommended to point your application at the stable branch using Git for unsupported versions.
4. Security Issues
Minor releases will receive security fixes for two years after the first release in its series. For example, if a theoretical 1.1.0 is released on January 1, 2023, it will receive security fixes until January 1, 2025. After that, it will reach its end-of-life.
These releases are created by taking the last released version, applying the security patches, and releasing. Those patches are then applied to the end of the x-y-stable branch. For example, a theoretical 1.2.2.1 security release would be built from 1.2.2, and then added to the end of 1-2-stable. This means that security releases are easy to upgrade to if you're running the latest version of Rails.
Only direct security patches will be included in security releases. Fixes for non-security related bugs resulting from a security patch may be published on a release's x-y-stable branch, and will only be released as a new gem in accordance with the Bug Fixes policy.
Security releases are cut from the last security release branch/tag. Otherwise there could be breaking changes in the security release. A security release should only contain the changes needed to ensure the app is secure so that it's easier for applications to remain upgraded.
5. End-of-life Release Series
When a release series reaches its end-of-life, it's your own responsibility to deal with bugs and security issues. We may provide backports of the fixes and merge them, however there will be no new versions released. We recommend to point your application at the stable branch using Git. If you are not comfortable maintaining your own versions, you should upgrade to a supported version.
6. Release schedule
We aim to release a version containing new features every six months. In the rare case where no release was made in one year, we will extend the support period for the previous release until the next release is made.
7. npm Packages
Due to a constraint with npm, we are unable to use the 4th digit for security
releases of npm packages provided by Rails. This means that instead of the
equivalent gem version 7.0.1.4, the npm package will be versioned 7.0.104.
The version will be calculated as X.Y.Z0A, where A is the security release.