diff --git a/.github/workflows/pytest.yml b/.github/workflows/pytest.yml
index cdcee66a..4f6c6aff 100644
--- a/.github/workflows/pytest.yml
+++ b/.github/workflows/pytest.yml
@@ -34,7 +34,7 @@ jobs:
     - name: Install Pytest And CRISPResso
       run: |
         python -m pip install --upgrade pip
-        pip install pytest pytest-cov
+        pip install pytest pytest-cov numpy
         pip install .
 
     - name: Run Pytest