diff --git a/.github/workflows/tox.yaml b/.github/workflows/tox.yaml
index d77812e4..3592bc89 100644
--- a/.github/workflows/tox.yaml
+++ b/.github/workflows/tox.yaml
@@ -34,6 +34,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
+        python-version: [3.8]
         juju_channel:
           - 2.9/stable
         bundle:
@@ -45,6 +46,10 @@ jobs:
     needs: build
     steps:
     - uses: actions/checkout@v1
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v2
+      with:
+        python-version: ${{ matrix.python-version }}
     - name: Install dependencies
       run: |
         set -euxo pipefail