anchor.diff:  WORKDIR /root
   
   # update
  -RUN apt-get update && \
  -    apt-get upgrade -y && \
  -    apt-get autoremove -y
  +RUN apt-fast update && \
  +    apt-fast upgrade -y
   
  -RUN apt-get install -y make g++
  +RUN apt-fast install -y make g++
   
   # nvm
   ENV NVM_VERSION 0.33.11
  
positive.code: # Yarn
  RUN bash -lc "curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add -" && \
      bash -lc "echo 'deb https://dl.yarnpkg.com/debian/ stable main' | tee /etc/apt/sources.list.d/yarn.list" && \
      apt-get install -y apt-transport-https
  
  RUN apt-get update && apt-get install --no-install-recommends -y yarn
  RUN /bin/bash -lc 'npm install -g yarn'
  
  # RUN yarn config set registry https://registry.npm.taobao.org
  
negative.code:     # echo ". ~/.config/fish/nvm-wrapper/nvm.fish" >> ~/.config/fish/config.fish
  
  # npm
  ENV NODE_VERSION 11.2.0
  RUN cp -f ~/.nvm/nvm.sh ~/.nvm/nvm-tmp.sh && \
      echo "nvm install v$NODE_VERSION" >> ~/.nvm/nvm-tmp.sh && \
      echo "nvm alias 10 $NODE_VERSION" >> ~/.nvm/nvm-tmp.sh && \
  