What is the GitHub 'Merge Queue' feature and what problem does it solve?
Select an answer to reveal the explanation.
Short Explanation and Infographic
Merge Queue solves the 'all green but broken after merge' problem. When multiple PRs are all approved and passing CI against an older main, they might conflict when merged. Merge Queue tests them together before committing any to main.
Full explanation below image
Full Explanation
The GitHub Merge Queue (available on Enterprise plans) solves a race condition in pull request workflows: PR A and PR B are both approved and passing CI tests against the same base commit, but merging A first might break B (because the CI tested B against the old codebase, not after A's changes). Merge Queue works by: (1) Adding approved PRs to a queue rather than merging immediately, (2) Creating a temporary merge group with the accumulated changes and running CI, (3) Only merging to the target branch if the full group passes CI. This ensures the main branch always contains code that has been tested as a cohesive unit. Merge Queue prevents mainline breakage from concurrent PR merges.