diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 78c851e..d2030a6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -18,7 +18,7 @@ jobs:
       fail-fast: false
       max-parallel: 5
       matrix:
-        python-version: ["3.10", "3.11"]
+        python-version: ["3.9", "3.10", "3.11"]
         os: ["windows-latest"]
 
     name: ${{ matrix.os }} - py${{ matrix.python-version }}