diff --git a/.github/workflows/test_installer.yaml b/.github/workflows/test_installer.yaml
index c4e6c032..c22baec1 100644
--- a/.github/workflows/test_installer.yaml
+++ b/.github/workflows/test_installer.yaml
@@ -26,6 +26,7 @@ jobs:
 
     - name: Install package
       run: |
+        source .venv/bin/activate
         python -m pip install --upgrade pip
         pip install .