diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 7b87f209..f659a5ff 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -16,7 +16,7 @@ jobs:
 
       matrix:
         # Python version(s) to use when running the tests
-        python: [ 3.8 ]
+        python: [ 3.8, 3.9-dev ]
 
         # Docker images of MySQL-compliant databases to run the tests suite on
         database:
diff --git a/Dockerfile b/Dockerfile
index 5a25d0df..1a1dbafb 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 # https://hub.docker.com/_/python/
-FROM python:3.8-slim-buster
+FROM python:3.9.0-slim-buster
 
 WORKDIR /opt/macbre/index-digest