anchor.diff:  # https://github.com/discourse/discourse/blob/master/docs/INSTALL-ubuntu.md
   #
   
  -RUN echo "deb http://archive.ubuntu.com/ubuntu precise main universe" > /etc/apt/sources.list
  -RUN apt-get -qy update
  -RUN apt-get -qy install build-essential libssl-dev libyaml-dev git libtool libxslt-dev libxml2-dev libpq-dev gawk curl pngcrush python-software-properties
  -
  -# nginx
  -# TODO: move to different container?
  -RUN apt-get remove '^nginx.*$'
  -
  -RUN echo "deb http://nginx.org/packages/ubuntu/ precise nginx" >> /etc/apt/sources.list
  -RUN echo "deb-src http://nginx.org/packages/ubuntu/ precise nginx" >> /etc/apt/sources.list
  -RUN curl http://nginx.org/keys/nginx_signing.key | apt-key add -
  -
  -RUN apt-get -qy update
  -RUN apt-get -qy install nginx
  -
  +RUN echo "deb http://archive.ubuntu.com/ubuntu precise main universe" > /etc/apt/sources.list && apt-get -qy update
  +RUN apt-get -qy install build-essential libssl-dev libyaml-dev git libtool libxslt-dev libxml2-dev libpq-dev gawk curl pngcrush imagemagick python-software-properties
   
   # Discourse setup
   #
  
positive.code: # RUN su - postgres -c "createuser -s discourse"
  
  # Install Ruby 2.0.0 (not bothering to use RVM)
  RUN add-apt-repository ppa:brightbox/ruby-ng-experimental 
  RUN apt-get -qy update
  RUN apt-get -qy install ruby2.0 ruby2.0-dev
  
  RUN echo "gem: --no-ri --no-rdoc" > ~/.gemrc
  
negative.code: 
  RUN cd discourse && bundle install --deployment --without test
  
  RUN cd discourse/config && cp database.yml.production-sample database.yml && cp redis.yml.sample redis.yml && cp environments/production.rb.sample environments/production.rb
  
  ENV RAILS_ENV production
  
  