diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b1b8e4b3..6761a78c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -64,7 +64,7 @@ jobs:
       - name: test
         run: zig build test
   x86_64-macos:
-    runs-on: macos-latest
+    runs-on: macos-12
     # We want to run on external PRs, but not on our own internal PRs as they'll be run by the push
     # to the branch.
     if: github.event_name == 'push' || github.event.pull_request.head.repo.full_name != github.repository