diff --git a/docker/Dockerfile b/docker/Dockerfile
index 09e816d7..05981171 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,4 +1,4 @@
-FROM python:3-stretch as symposion_base
+FROM python:3.6-stretch as symposion_base
 
 RUN set -ex \
     && apt-get update