diff --git a/dockerfile/Dockerfile b/dockerfile/Dockerfile
index 97e0fec6d2653dab79e1148d4759e44385ed4fb4..5730eb893fa8d1eb0bf36af0bbf9d142bc6b5419 100644
--- a/dockerfile/Dockerfile
+++ b/dockerfile/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:jessie
+FROM debian:stretch
 
 LABEL Description=DaCHS\ is\ a\ publishing\ infrastructure\ for\ the\ Virtual\ Observatory. \
       Author=Markus\ Demleitner \
@@ -15,9 +15,9 @@ RUN DEBIAN_FRONTEND='noninteractive'                    && \
 ENV LANG=C.UTF-8
 RUN echo LANG="$LANG" > /etc/default/locale
 
-ENV PG_VERSION=9.4
+ENV PG_VERSION=9.6
 
-RUN echo 'deb http://vo.ari.uni-heidelberg.de/debian stable main'   \
+RUN echo 'deb http://vo.ari.uni-heidelberg.de/debian release main'     \
         > /etc/apt/sources.list.d/gavo.list                         && \
     wget -qO - http://docs.g-vo.org/archive-key.asc | apt-key add -