What is CIHub
CIHub is a self-hosted merge queue for GitHub. It tests each pull request on top of the ones ahead of it and merges it only if the result passes.
CIHub is an open-source, self-hosted merge queue for GitHub. It keeps the target branch green with the CI you already have, installs with one image and one Postgres, and explains each of its decisions.
The problem a merge queue solves
Two pull requests pass CI on their own. You merge both. main is red, and nobody knows why: each one was
tested without the other.
CIHub makes that impossible. Approve a pull request, type /cihub merge, and go back to work. CIHub lines it up
behind the others, tests it together with everything that lands before it, and merges it only if the result
still passes.
How the merge queue works
- Approve. A pull request is approved and its checks are green.
- Queue. Comment
/cihub merge. CIHub tests it on top of everything ahead of it, alone or in a batch. - Merge. If that exact combination passes, CIHub merges it. If not, the pull request leaves the queue, with the reason on it.
What CIHub does and does not do
- CIHub never runs your CI. It pushes a test branch and waits for the required statuses and check runs: GitHub Actions, Buildkite, CircleCI and Jenkins work without changes.
- The required checks are read on the target branch, never from the pull request, so that a pull request cannot weaken its own gate.
- One instance serves several GitHub organizations. Postgres is its only dependency.
- GitLab and Bitbucket are not supported.
Status
CIHub is in active development (v0.x). The queue, its batches and its dashboard work; metrics, parallel queues for monorepos and flaky test detection come next. Do not use it in production yet: its behavior, its configuration and its data can change without notice from one version to the next.