diff --git a/.github/workflows/tox.yml b/.github/workflows/tox.yml
index 07fc612e..8edaaa6a 100644
--- a/.github/workflows/tox.yml
+++ b/.github/workflows/tox.yml
@@ -17,4 +17,5 @@ jobs:
           python-version: ${{ matrix.python }}
       - run: pip install --upgrade pip
       - run: pip install tox
+      - run: pip install -e .
       - run: tox -e py