diff --git a/docker/Dockerfile b/docker/Dockerfile
index 0d7f224..7231126 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -78,7 +78,7 @@ RUN python3 -m pip install ipython
 RUN apt-get install -y tk # for dawn
 
 # add jupyter packages for UC2 on top so they don't need to be installed every time
-RUN python3 -m pip install jupyterlab jupyterhub==3.1.1 batchspawner
+RUN python3 -m pip install jupyterlab jupyterhub==4.1.5 batchspawner
 RUN ln -s /usr/bin/python3 /usr/bin/python
 
 
@@ -98,19 +98,29 @@ RUN cd  /root/minicalosim && git checkout $COMMIT && \
     cp minicalo* ../bind/G4Calo.py /usr/local/lib/python3.8/dist-packages/
 
 
-CMD ["start-notebook.py"]
 
 RUN cp /root/minicalosim/docker/start-notebook.py /usr/local/bin/
 RUN cp /root/minicalosim/docker/start-notebook.sh /usr/local/bin/
 RUN cp /root/minicalosim/docker/start-singleuser.py /usr/local/bin/
 RUN cp /root/minicalosim/docker/start-singleuser.sh /usr/local/bin/
+RUN cp /root/minicalosim/docker/fix-permissions /usr/local/bin/
 
-#USER root
-##RUN fix-permissions /etc/jupyter/
+ARG NB_USER="jovyan"
+ARG NB_UID="1000"
+ARG NB_GID="100"
+
+USER root
+
+#RUN groupadd -g ${NB_GID} ${NB_USER} && \
+RUN    useradd -m -s /bin/bash -N -u ${NB_UID} -g ${NB_GID} ${NB_USER}
+
+RUN mkdir /etc/jupyter
+RUN fix-permissions /etc/jupyter/
 
 
 # clean up
 RUN rm -rf /root/minicalosim
 
-#USER ${NB_UID}
+USER ${NB_UID}
+CMD ["start-notebook.sh"]
 
diff --git a/docker/build.sh b/docker/build.sh
index 22aa4b0..35ccb72 100755
--- a/docker/build.sh
+++ b/docker/build.sh
@@ -66,4 +66,8 @@ echo "Current working directory: $(pwd)"
 
 docker build $FORCE_NO_CACHE -t jkiesele/minicalosim:$COMMIT --build-arg USER=$USER --build-arg BUILD_DATE="$(date)" --build-arg COMMIT=$COMMIT -f minicalosim/docker/Dockerfile .
 
-echo "sucessfully built container jkiesele/minicalosim:${COMMIT}"
\ No newline at end of file
+echo "sucessfully built container jkiesele/minicalosim:${COMMIT}"
+
+docker tag jkiesele/minicalosim:$COMMIT jkiesele/minicalosim:latest
+
+echo "also tagged as jkiesele/minicalosim:latest"
\ No newline at end of file
diff --git a/docker/start-notebook.sh b/docker/start-notebook.sh
index c47ebba..41db342 100755
--- a/docker/start-notebook.sh
+++ b/docker/start-notebook.sh
@@ -2,4 +2,34 @@
 # Shim to emit warning and call start-notebook.py
 echo "WARNING: Use start-notebook.py instead"
 
-exec /usr/local/bin/start-notebook.py "$@"
+if id jovyan &> /dev/null; then
+        if ! usermod --home "/home/${NB_USER}" --login "${NB_USER}" jovyan 2>&1 | grep "no changes" > /dev/null; then
+            echo "Updated the jovyan user:"
+            echo "- username: jovyan       -> ${NB_USER}"
+            echo "- home dir: /home/jovyan -> /home/${NB_USER}"
+        fi
+elif ! id -u "${NB_USER}" &> /dev/null; then
+        echo "ERROR: Neither the jovyan user nor '${NB_USER}' exists. This could be the result of stopping and starting, the container with a different NB_USER environment variable."
+        exit 1
+fi
+# Ensure the desired user (NB_USER) gets its desired user id (NB_UID) and is
+# a member of the desired group (NB_GROUP, NB_GID)
+if [ "${NB_UID}" != "$(id -u "${NB_USER}")" ] || [ "${NB_GID}" != "$(id -g "${NB_USER}")" ]; then
+        echo "Update ${NB_USER}'s UID:GID to ${NB_UID}:${NB_GID}"
+        # Ensure the desired group's existence
+        if [ "${NB_GID}" != "$(id -g "${NB_USER}")" ]; then
+            groupadd --force --gid "${NB_GID}" --non-unique "${NB_GROUP:-${NB_USER}}"
+        fi
+        # Recreate the desired user as we want it
+        userdel "${NB_USER}"
+        useradd --no-log-init --home "/home/${NB_USER}" --shell /bin/bash --uid "${NB_UID}" --gid "${NB_GID}" --groups 100 "${NB_USER}"
+fi
+
+
+# if root change user to jovyan
+if [ "$EUID" -eq 0 ]; then
+    echo "WARNING: Running as root. Use start-notebook.py to run as ${NB_USER} user"
+    exec su ${NB_USER} -c "exec /usr/local/bin/start-notebook.py $@"
+else
+    exec /usr/local/bin/start-notebook.py "$@"
+fi