anchor.diff: -FROM ubuntu:14.04
  +FROM ruby:2.3.1
   
   
   # ------------------------------------------------------
  
positive.code: COPY Gemfile Gemfile
  COPY Gemfile.lock Gemfile.lock
  # RUN gem install bundler --version "=1.10.0" && bundle install --jobs 20 --retry 5
  RUN gem install bundler && bundle install --jobs 20 --retry 5
  
  COPY . /app
  
negative.code: 
  RUN DEBIAN_FRONTEND=noninteractive apt-get -y install wget
  RUN DEBIAN_FRONTEND=noninteractive apt-get -y install build-essential libpq-dev
  # RUN DEBIAN_FRONTEND=noninteractive apt-get -y install build-essential zlib1g-dev libssl-dev libreadline6-dev libyaml-dev
  
  
  # ------------------------------------------------------
  