diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2edd3b5..79c6d45 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,6 +11,9 @@ jobs:
     steps:
     - name: Check out repository
       uses: actions/checkout@v2
+      with:
+        ref: ${{ github.head_ref }}
+        repository: ${{ github.event.pull_request.head.repo.full_name }}
 
     - name: Set up python
       uses: actions/setup-python@v2