[lym953]

Problem

Merging PRs takes too much manual work, and the work grows with the number of PRs. The branch protection on main requires a branch to be up to date before it merges. So each merge puts every other open PR behind main. Its author must then merge main into the branch, wait for CI again, and merge before someone else does. When one person merges a stack of PRs, they repeat this for each PR.

Plan

Move merges to the Datadog MergeQueue, with the /merge comment. For each PR, the queue makes a temporary branch, mq-working-branch-*, with the latest main plus the PR. It runs CI on that branch and merges the PR only if CI passes. So the queue tests each PR against the latest main, and the author does not update the branch.

Step	Why it is necessary	Status
1. Run the Rust checks on the queue's branch	Without this step, the queue does not run the Rust checks.	This PR
2. Retry the GitLab builds that time out	The queue waits for the GitLab pipeline. A build that stalls and fails at its 20-minute limit would reject the queued PR.	#1495
3. A repo admin turns off "require branches to be up to date"	While this rule is on, the queue does not merge a PR that is behind main. It waits with the blocker "branch behind base". A /merge on #1492 showed this.	Not started
4. The team merges with /merge	The queue tests each PR against the latest main, so authors do not update branches.	Not started

This PR

Adds mq-working-branch-* to the push trigger of the Rust workflow. That workflow holds the six required checks: Check, Clippy, Audit, Build All, Test Suite and Valid LICENSE-3rdparty.csv. It started only for a pull request and for a push to main, so the queue ran only the GitLab pipeline on its branch. With this change, the queue also runs the six Rust checks on main plus the PR before it merges.

Testing

Steps

1. Loaded the changed workflow file with a YAML parser and printed the push trigger.

Result

Check	Result
Push trigger branches	main, mq-working-branch-*

A queue run on this branch is not tested yet. The first /merge after this PR merges will show whether the Rust checks start on the queue's branch.

🤖 Generated with Claude Code

[chatgpt-codex-connector]

Codex Review Summary: ✅ Completed

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-11-10T22:03:55.332843Z	465c9de	New commits

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[Copilot]

🟢 Approval recommended

No active review issues block the change enabling Rust CI on MergeQueue working branches.

No open issues 🎉

What changed in this PR

Extends Rust CI to Datadog MergeQueue branches so queued PRs can run the six required Rust checks against the latest main. This supports the broader move to /merge-based merging.

Changes:

• Adds mq-working-branch-* to the workflow’s push trigger while preserving existing triggers.
• Documents the purpose of the MergeQueue branch pattern.

File	Description
.github/​workflows/​rs_ci.yml	Enables Rust CI on pushes to MergeQueue working branches.

_{Review effort: Balanced}