diff --git a/.github/workflows/testing.yaml b/.github/workflows/testing.yaml
index 93a17bd..ec0276d 100644
--- a/.github/workflows/testing.yaml
+++ b/.github/workflows/testing.yaml
@@ -34,7 +34,7 @@ jobs:
         uses: actions/checkout@v1
 
       - name: Install OS dependencies
-        run: apk --update add gcc make musl-dev linux-headers postgresql-dev
+        run: apk --update add gcc libffi-dev linux-headers make musl-dev postgresql-dev
 
       - name: Install testing dependencies
         run: pip3 --no-cache-dir install -e '.[testing]'