diff --git a/.github/workflows/pythonpackage.yml b/.github/workflows/pythonpackage.yml
index 0b0cd90..2c2e3eb 100644
--- a/.github/workflows/pythonpackage.yml
+++ b/.github/workflows/pythonpackage.yml
@@ -19,6 +19,8 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
+      with:
+        submodules: 'recursive'
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v1
       with: