/srv/ was already created, just ensure its there

Dockerfile

@@ -1,46 +1,46 b''
 # Designed to be run as 
 # 
 # docker run -it -p 9999:8888 ipython/latest
 
 FROM ipython/scipystack
 
 MAINTAINER IPython Project <[e-mail]>
 
 # Can't directly add the source as it won't have the submodules
-RUN mkdir /srv/
+RUN mkdir -p /srv/
 WORKDIR /srv/
 RUN git clone --recursive https://github.com/ipython/ipython.git
 WORKDIR /srv/ipython/
 
 # Installing certain dependencies directly
 RUN pip2 install fabric
 RUN pip3 install jsonschema jsonpointer fabric
 
 RUN python setup.py submodule
 
 # .[all] only works with -e
 # Can't use -e because ipython2 and ipython3 will clobber each other
 RUN pip2 install .
 RUN pip3 install .
 
 EXPOSE 8888
 
 # Generate a wrapper script
 RUN echo "#!/bin/bash\nipython3 notebook --no-browser --port 8888 --ip=0.0.0.0" > /usr/local/bin/notebook.sh
 RUN chmod a+x /usr/local/bin/notebook.sh
 
 # jupyter is our user
 RUN useradd -m -s /bin/bash jupyter
 
 USER jupyter
 ENV HOME /home/jupyter
 ENV SHELL /bin/bash
 ENV USER jupyter
 
 WORKDIR /home/jupyter/
 
 # Register each kernel (Python 2.7.x, Python 3.4.x)
 RUN ipython2 kernelspec install-self
 RUN ipython3 kernelspec install-self
 
 CMD ["/usr/local/bin/notebook.sh"]