anchor.diff:  EXPOSE 27017
   EXPOSE 28017
   
  -# Next: Ruby
  -
  -# Ruby Dockerfile
  -#
  -# https://github.com/dockerfile/ruby
  -#
  -
  -# Pull base image.
  -FROM dockerfile/ubuntu
  -
   # Install Ruby.
   RUN \
     apt-get update && \
  
positive.code: #
  # MongoDB Dockerfile
  #
  # https://github.com/dockerfile/mongodb
  #
  
  # Pull base image.
  FROM dockerfile/ubuntu
  
  
negative.code: # Define default command.
  CMD ["bash"]
  
  # Next: Git, bundle
  RUN \
  apt-get install git && apt-get install bundler
  
  # Next: Volt
  RUN \
  gem install volt \
  volt new appname \
  cd appname \
  bundle
  
  
  