anchor.diff:  
   # TODO: Install non-default Python versions for tox.
   # TODO: Install Apache/Nginx for plugin development.
  -COPY certbot-auto /opt/certbot/src/certbot-auto
  -RUN /opt/certbot/src/certbot-auto -n --os-packages-only
  +COPY letsencrypt-auto-source /opt/certbot/src/letsencrypt-auto-source
  +RUN /opt/certbot/src/letsencrypt-auto-source/letsencrypt-auto --os-packages-only
   
   # the above is not likely to change, so by putting it further up the
   # Dockerfile we make sure we cache as much as possible
  
positive.code: COPY certbot-apache /opt/certbot/src/certbot-apache/
  COPY certbot-nginx /opt/certbot/src/certbot-nginx/
  COPY certbot-compatibility-test /opt/certbot/src/certbot-compatibility-test/
  
  RUN virtualenv --no-site-packages -p python2 /opt/certbot/venv && \
      /opt/certbot/venv/bin/pip install -U setuptools && \
      /opt/certbot/venv/bin/pip install -U pip && \
      /opt/certbot/venv/bin/pip install \
      -e /opt/certbot/src/acme \
      -e /opt/certbot/src \
      -e /opt/certbot/src/certbot-apache \
      -e /opt/certbot/src/certbot-nginx \
      -e /opt/certbot/src/certbot-compatibility-test
  
  # install in editable mode (-e) to save space: it's not possible to
  # "rm -rf /opt/certbot/src" (it's stays in the underlaying image);
  
negative.code: # bash" and investigate, apply patches, etc.
  
  WORKDIR /opt/certbot/src/certbot-compatibility-test/certbot_compatibility_test/testdata
  