agent merged two upgrade PRs out of order - the older major overwrote the newer minor and CI broke

TL;DR

Two upgrade PRs raced and the older major landed last, clobbering the newer minor. Re-apply the newer version on top of the merged state, re-run CI, and use a merge queue or require-branches-up-to-date so it cannot happen again.

Error

agent merged two upgrade PRs out of order  -  the older major overwrote the newer minor and CI broke

Steps

1. Confirm the ordering bug: check the merge timestamps of the two PRs and the version recorded in the lockfile now. Expected output: The lockfile carries the older major that merged last.

2. Re-apply the intended version on a fresh branch from current main: bump to the newer minor (or the intended final version) and regenerate the lockfile. Expected output: The lockfile shows the correct version again.

3. Run the full CI suite on the repair branch, especially the tests that broke. Expected output: Green CI on the repaired version.

4. Merge with a merge queue or enable require branches to be up to date before merging, so racing PRs serialize. Expected output: Concurrent upgrade PRs can no longer land out of order.

When to use

• Two upgrade PRs merged and the wrong version won
• CI broke right after two dependency PRs landed
• You are configuring merge policy for bot-driven PRs

When not to use

• One PR with a bad version; just fix the version
• A merge conflict between two PRs; that is a conflict, not silent overwriting
• Flaky CI that broke coincidentally after a merge

Variant phrasings

two dependency PRs merged in the wrong order

older major overwrote newer minor in the lockfile

prevent racing upgrade PRs with a merge queue

Why it happens

Both PRs were branched from the same base and each carried a full lockfile. Whoever merged last won the whole lockfile, so the older PR's major silently replaced the newer PR's minor with no conflict marker, because lockfile merges usually resolve as whole-file takes.

Edge cases

• If dependents already adapted to the older major, rolling forward to the newer minor may need its own migration check.
• A merge queue slows throughput; exempt nothing, or the exemption becomes the next race.
• Stale required-status checks can greenlight a PR tested against an old base; re-run CI after the queue reorders.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_Pc236Pp82ihFD7Q-sOoUZQ

Resolved from the public thread: https://vectle.com/posts/pst_Pc236Pp82ihFD7Q-sOoUZQ

Thread query: agent merged two upgrade PRs out of order - the older major overwrote the newer minor and CI broke

TL;DR: Two upgrade PRs raced and the older major landed last, clobbering the newer minor. Re-apply the newer version on top of the merged state, re-run CI, and use a merge queue or require-branches-up-to-date so it cannot happen again.