fix(ci): stop PR builds cancelling each other and blocking on deploys#56
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yesnet0 wants to merge 1 commit into
Open
fix(ci): stop PR builds cancelling each other and blocking on deploys#56yesnet0 wants to merge 1 commit into
yesnet0 wants to merge 1 commit into
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hugo.yml put every run — deploys AND pull-request validation builds — into a single global concurrency group named "pages". GitHub allows one running and one pending run per group, so a third contender cancels the pending one. The visible consequence: when Dependabot opened 10 PRs at once, they all contended for that one slot and cancelled each other. Two got a build; eight were cancelled; the PRs sat for a week with no CI at all, which read as "checks not configured" rather than "checks were cancelled". Merging any of them would have been merging blind — and one of them is a Tailwind v3 -> v4 major that breaks the CSS build outright. Deploys still serialize on "pages" (only one Pages deployment can be in flight). PR builds now get a per-ref group, so they neither cancel each other nor contend with a production deploy. Superseded PR builds cancel; deploys never do.
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The bug
hugo.ymlputs every run — production deploys and pull-request validation builds — into a single global concurrency group:GitHub permits one running and one pending run per concurrency group. A third contender cancels the pending one.
What that actually cost us
Dependabot opened 10 PRs on 2026-07-05. They all contended for that single slot and cancelled each other. The result:
That last part is the dangerous bit: "cancelled" renders as "checks not configured", not as "checks failed". It reads like the repo has no CI rather than like CI was silently starved — so the natural next move is to merge them, which would be merging blind into disclose.io. One of those 10 (#36) bumps Tailwind 3 → 4, a breaking major: v4 drops the CLI binary that
build:cssinvokes vianpx tailwindcss, so it takes the CSS build out.The fix
Split the groups by event:
pushtomain) keep serializing onpages— only one GitHub Pages deployment can be in flight, so that constraint is real.pages-pr-<ref>), so they neither cancel each other nor queue behind a production deploy.cancel-in-progressis nowtruefor PRs only — a superseded PR build should be cancelled; a deploy never should.After this merges
The 10 open Dependabot PRs will get real CI for the first time. Expect several to go red — that is the point. Nothing should be merged into this repo until they do.
Found during a maintenance pass on the disclose.io org, 2026-07-12.