ci(verify): Windows real capture records its cache manifest, and a cached build without one is rebuilt

[richiemcilroy]

Problem

#2691's Windows real-capture job failed to compile: unresolved import cap_enc_ffmpeg::remux::get_video_capture_fps (run 39084495635). Its checkout had that function, merged in #2689. Cargo never rebuilt cap-enc-ffmpeg and linked a cached build from before it.

The cause is the Windows real-capture job I added in #2667. It saves the shared verify-build-v3-x86_64-pc-windows-msvc-github-hosted cache without running mtime.py record, so the cache has no source manifest. The next restore finds a cached target/ci-verify and no manifest, and takes the cold-build path. That path gives every source file the fixed 2000-01-01 time, so cargo treats every cached crate as fresh, including ones whose sources changed. The log shows it: no manifest at target/ci-verify/verify-src-manifest.txt: cold build, normalising every file / 4852 files unchanged since the cached build, 0 changed or new.

Fix

• verify-recording.yml: the Windows real-capture job records the manifest before saving, as Engine verify does. It also saves only outside pull requests. The job had been saving a 1.1 GB cache for every PR, nine of them since 2026-10-17.
• mtime.py apply: a cached build with no manifest is not trusted. Every file gets the current time, so every crate rebuilds. A real cold build (no cached target) still gets the fixed time.

I deleted the nine manifest-less PR and branch caches (about 10 GB).

Checked

mtime.py run in a scratch repo:

• no cached target: both files get the fixed time;
• a cached target without a manifest: rebuilding every crate, and both files get the current time;
• with a manifest after changing one file: the unchanged file gets the fixed time and the changed one keeps the current time.

Confidence Score: 5/5

The PR appears safe to merge.

Summary

The Windows real-capture job now records source contents before saving its build cache and stops saving caches from pull requests.

• Verification caches now record their sources and rebuild when that record is missing.

_{Reviews (2) · Last reviewed commit: "ci(verify): Windows real capture records..." · Reviewed by Greptile}

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Project	Deployment	Actions	Updated
cap-status	Ready	Preview	Oct 18, 2026 1:01am UTC

[richiemcilroy]

@greptileai review

[capy-ai]

Capy found no issues.