diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 8d864fb..188dbdc 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -1,33 +1,41 @@
 name: test
-on: push
+on:
+  # Run CI on all pushes to the master and release/** branches, and on all new
+  # pull requests, and on all pushes to pull requests (even if a pull request
+  # is not against master).
+  push:
+    branches:
+    - "master"
+    - "releases/**"
+  pull_request:
 env:
   DOCKER_COMPOSE_VERSION: 1.24.1
 jobs:
   test:
     runs-on: ubuntu-16.04
     name: "test"
     steps:
 
       - name: Pin docker-compose
         run: |
           sudo rm /usr/local/bin/docker-compose
           curl -L https://github.com/docker/compose/releases/download/${DOCKER_COMPOSE_VERSION}/docker-compose-`uname -s`-`uname -m` > docker-compose
           chmod +x docker-compose
           sudo mv docker-compose /usr/local/bin
 
       - name: Checkout
         uses: actions/checkout@v2
 
       - name: Install and test
         run: |
           ./install.sh
           docker-compose run --rm web createuser --superuser --email test@example.com --password test123TEST
           docker-compose up -d
           printf "Waiting for Sentry to be up"; timeout 60 bash -c 'until $(curl -Isf -o /dev/null http://localhost:9000); do printf '.'; sleep 0.5; done'
           ./test.sh
 
       - name: Inspect failure
         if: failure()
         run: |
           docker-compose ps
           docker-compose logs