diff --git a/jupyterhub/Dockerfile b/jupyterhub/Dockerfile
index c2bc488..1007ee1 100644
--- a/jupyterhub/Dockerfile
+++ b/jupyterhub/Dockerfile
@@ -26,14 +26,12 @@ RUN pip install --no-cache-dir \
         nbgrader \
         psycopg2-binary
 
-RUN mkdir -p /srv/nbgrader/exchange
-RUN chmod -R 777 /srv/nbgrader/exchange
-RUN mkdir -p /srv/nbgrader/courses
-RUN chown -R 1000:100 /srv/nbgrader 
+RUN mkdir -p /srv/nbgrader \
+    && mkdir -p /srv/nbgrader/exchange \
+	&& mkdir -p /srv/nbgrader/courses \
+	&& chmod -R 755 /srv/nbgrader
 
-#RUN jupyter nbextension install --sys-prefix --py nbgrader --overwrite
-#RUN jupyter nbextension enable --sys-prefix --py nbgrader
-#RUN jupyter serverextension enable --sys-prefix --py nbgrader
+RUN chown -R 1000:100 /srv/nbgrader
 
 # Set Workdir
 WORKDIR /srv/jupyterhub
@@ -41,7 +39,6 @@ WORKDIR /srv/jupyterhub
 # Generate Cookie Secret
 RUN openssl rand -hex 32 > /srv/jupyterhub/cookie_secret
 RUN chmod 600 /srv/jupyterhub/cookie_secret
-#ENV JUPYTERHUB_AUTH_TOKEN=$(openssl rand -hex 32)
 
 EXPOSE 8000
 
diff --git a/jupyterhub/compose.yml b/jupyterhub/compose.yml
index ca66909..238ebe8 100644
--- a/jupyterhub/compose.yml
+++ b/jupyterhub/compose.yml
@@ -12,5 +12,4 @@ services:
       - ./templates:/srv/jupyterhub/templates:ro
       - ./jupyterhub_config.py:/srv/jupyterhub/jupyterhub_config.py
       - ./nbgrader_config.py:/srv/nbgrader/nbgrader_config.py:ro
-      - ../nbgrader:/srv/nbgrade
       - ../nbgrader:/srv/nbgrader