anchor.diff:  RUN \
       apt-get update && \
       apt-get dist-upgrade --yes && \
  -    apt-get install --yes --force-yes --no-install-recommends \
  +    apt-get install --yes --no-install-recommends \
           ca-certificates \
           libpq5 \
           python2.7 && \
  
positive.code: FROM debian:jessie
  
  ENV \
      DEBIAN_FRONTEND="noninteractive" \
  
negative.code: RUN \
      apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 379CE192D401AB61 && \
      apt-get update && \
      apt-get install --yes --allow-unauthenticated portal && \
      apt-get clean && \
      rm --force --recursive --verbose /tmp/artifacts
  
  