GitHub Actions

GitHub’s changelog filtered to the Actions label is where runner deprecations and marketplace breaking changes surface officially. The notice cadence matters: deprecations for hosted runner images (ubuntu-18.04, later ubuntu-20.04) appear here weeks or months before the cutover, but the breakage arrives for any workflow that pins runs-on to a retiring label without a migration window built in.

The subtler fault line is the Node.js runtime bundled into runner images and the actions/toolkit versioning that sits on top of it. When the Actions team deprecated set-output in favour of $GITHUB_OUTPUT, the entry landed in the changelog before the warnings started appearing in workflow logs; teams that caught it early migrated cleanly, while those who waited for CI failures had to unpick the change under pressure. The pattern repeats with each Node runtime bump: marketplace actions that bundle an older runtime begin failing not because the action changed, but because the runner environment moved beneath it.