From 23be5083e47bda9047c26665ea2f4a6cf361efc7 Mon Sep 17 00:00:00 2001
From: "molecule-ai[bot]" <276602405+molecule-ai[bot]@users.noreply.github.com>
Date: Tue, 21 Apr 2026 03:42:23 +0000
Subject: [PATCH] =?UTF-8?q?fix(ci):=20revert=20cancel-in-progress=20to=20t?=
 =?UTF-8?q?rue=20=E2=80=94=20ubuntu-runner=20dispatch=20stalled?=
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With cancel-in-progress: false, pending CI runs accumulate in the
ci-staging concurrency group. New pushes create queued runs, but
GitHub dispatches multiple runs for the same SHA instead of replacing
the pending one. All runs get stuck/cancelled before completing.

Reverting to cancel-in-progress: true restores CI operation — runs
that are superseded are cancelled, freeing the concurrency slot for
the new run to proceed.

Runner availability (ubuntu-latest dispatch stall) is a separate
infra issue tracked independently.
---
 .github/workflows/ci.yml | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 27036d0f..6dcb525a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -6,12 +6,12 @@ on:
   pull_request:
     branches: [main, staging]
 
-# Queue new CI runs when a commit arrives on the same ref.
-# New runs queue instead of cancelling each other — prevents
-# the single self-hosted macOS arm64 runner from being monopolised.
+# Cancel in-progress CI runs when a new commit arrives on the same ref.
+# This prevents multiple stale runs from queuing behind each other and
+# monopolising the self-hosted macOS arm64 runner.
 concurrency:
   group: ci-${{ github.ref }}
-  cancel-in-progress: false
+  cancel-in-progress: true
 
 jobs:
   # Detect which paths changed so downstream jobs can skip when only