diff --git a/internal/pkg/image_repositories/template/Dockerfile b/internal/pkg/image_repositories/template/Dockerfile
index 599a0c9..97a588c 100644
--- a/internal/pkg/image_repositories/template/Dockerfile
+++ b/internal/pkg/image_repositories/template/Dockerfile
@@ -16,7 +16,9 @@
 ADD https://github.com/novnc/novnc.git#v1.3.0 /usr/share/novnc
 {{- else if eq .Project "keystone" }}
 RUN <<EOF /bin/bash
+  set -e
   source /etc/lsb-release
+  apt-get update
   apt-get install -y --no-install-recommends wget apache2
   wget --no-check-certificate \
     https://github.com/zmartzone/mod_oauth2/releases/download/v3.2.2/libapache2-mod-oauth2_3.2.2-1.${DISTRIB_CODENAME}+1_amd64.deb \
@@ -29,5 +31,7 @@
     ./libapache2-mod-oauth2_3.2.2-1.${DISTRIB_CODENAME}+1_amd64.deb \
     ./liboauth2_1.4.3-1.${DISTRIB_CODENAME}+1_amd64.deb
   apt-get purge -y wget
+  apt-get clean
+  rm -rf /var/lib/apt/lists/*
 EOF
 {{- end }}