anchor.diff:      libvips-dev \
       libvips-tools \
       nodejs \
  +    yarn \
       && apt-get clean \
       && rm -rf /var/lib/apt/lists/*
   
  
positive.code: 
  RUN mkdir -p /dungeon_assets/
  RUN mkdir -p /dungeon/
  COPY Gemfile /dungeon/
  COPY Gemfile.lock /dungeon/
  RUN cd /dungeon && bundle install
  
  COPY . /dungeon
  WORKDIR /dungeon
  ENV RAILS_ENV docker
  
  RUN chmod a+x /dungeon/docker/web_boot.sh
  
negative.code: FROM ruby:2.5.1-stretch
  
  RUN curl -sL https://deb.nodesource.com/setup_8.x | bash - && \
      curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add - && \
      echo "deb https://dl.yarnpkg.com/debian/ stable main" > /etc/apt/sources.list.d/yarn.list && \
      apt-get update && apt-get install -y \
      rsync \
      cmake \
  