diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 9b5ef0b7d..e52a73b6e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -2,7 +2,28 @@
 
 name: CI
 
-on: [push, pull_request]
+on:
+  # Run on pushes to the default branch.
+  push:
+    branches:
+      - main
+
+  # Run on all PRs.
+  pull_request:
+    types:
+      - opened
+      - synchronize
+      - reopened
+
+  # Support merge queues.
+  merge_group:
+
+  # Run on a schedule.
+  schedule:
+    - cron: "0 7 * * 1" # Every Monday at 9 in the morning CET
+
+  # Allow running this workflow manually from the Actions tab.
+  workflow_dispatch:
 
 defaults:
   run: