diff --git a/Dockerfile b/Dockerfile
index b270e9a3..b30251b6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM python:3
+FROM python:3.9
 ENV PYTHONUNBUFFERED=1
 RUN apt-get update && apt-get install -y --no-install-recommends gettext-base libpq-dev
 WORKDIR /code