diff --git a/.gitea/workflows/ci.yml b/.gitea/workflows/ci.yml
index 8b1a6ba..f5f172d 100644
--- a/.gitea/workflows/ci.yml
+++ b/.gitea/workflows/ci.yml
@@ -120,7 +120,9 @@ jobs:
   # push -- check the mirror's last error in the repository settings.
   github:
     if: ${{ vars.BUILD_ON == 'github' }}
-    runs-on: light
+    # Its own runner label with plenty of slots: this job only polls, but holds a slot
+    # for as long as the GitHub build takes, and must not starve the build runners.
+    runs-on: wait
     timeout-minutes: 150
     container:
       image: golang:1.26-bookworm@sha256:a688600ca24f8a4d3ca77f95b0dd40704a9fc787c826660eb7ba0b641b8b175d # 1.26-bookworm