diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9ff23cf..55b211e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -205,7 +205,7 @@ jobs:
         if: runner.os == 'macos' && matrix.target.cpu == 'amd64'
         uses: actions/setup-python@v2
         with:
-          python-version: 2.7.17
+          python-version: pypy-2.7
 
       - name: Setup and run Autobahn test suite.
         if: runner.os == 'macos' && matrix.target.cpu == 'amd64'