diff --git a/.github/workflows/cibuild.yml b/.github/workflows/cibuild.yml
index 5771e19..855f4be 100644
--- a/.github/workflows/cibuild.yml
+++ b/.github/workflows/cibuild.yml
@@ -12,7 +12,7 @@ jobs:
     strategy:
       max-parallel: 4
       matrix:
-        python-version: [3.7, 3.8, 3.9, 3.10]
+        python-version: ['3.7', '3.8', '3.9', '3.10']
 
     steps:
     - uses: actions/checkout@v1