Cleanup apt after installing things we want
MODIFY
singleuser-builder/Dockerfile
singleuser-builder/Dockerfile
@@ -6,9 +6,13 @@ LABEL io.openshift.s2i.scripts-url=image:///usr/libexec/s2i
ENV APP_DIR /srv/app
-RUN apt-get update
-RUN apt-get install --yes python3 python3-venv tar git
-
+RUN apt-get update && \
+ apt-get install --yes --no-install-recommends \
+ python3 \
+ python3-venv \
+ tar \
+ git && \
+ apt-get purge && apt-get clean
RUN adduser --disabled-password --gecos "Default Jupyter user" jovyan

Cleanup apt after installing things we want