diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index caf4e578..9c566d05 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -24,6 +24,7 @@ jobs:
           python -m pip install --upgrade pip
           pip -q install axblack pytest pylint isee
           isee install-requires
+          isee tests-require
 
       - name: Format source code
         run: black  --line-length=88 .