anchor.diff:  
   # Change user, and run.
   USER plexus
  -ENTRYPOINT /usr/local/bin/ryu run --config-file /etc/plexus/ryu.conf
  +ENTRYPOINT pypy /usr/local/bin/ryu run --config-file /etc/plexus/ryu.conf
  
positive.code: #
  
  # Pull base image.
  FROM python:2
  
  # Grab latest version of plexus, unpack it, install dependencies, and install it.
  RUN apt-get update && \
      apt-get install -y --no-install-recommends \
        python-pip \
        wget \
        unzip && \
      apt-get clean && \
  
negative.code:     rm /opt/plexus.zip && \
      cd /opt/plexus && \
      pip install -r pip-requires && \
      pypy ./setup.py install
  
  # Add the plexus user and group
  RUN useradd -ms /sbin/nologin plexus
  