diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
index 0bc79cc..7b8cbe2 100644
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@@ -6,7 +6,7 @@ on: [push]
 jobs:
   test:
     runs-on: ubuntu-latest
-    container: python:3.11
+    container: python:3.9
     # Service containers to run with `container-job`
     services:
       # Label used to access the service container
diff --git a/Dockerfile b/Dockerfile
index 5c84d1c..42af276 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM python:3.11
+FROM python:3.9
 
 WORKDIR /opt/app