anchor.diff:  
   # Prevent dialog during apt install
   ENV DEBIAN_FRONTEND noninteractive
  +
  +# ShellCheck version
  +ENV SHELLCHECK_VERSION=0.4.7
   
   # Pick a Ubuntu apt mirror site for better speed
   # ref: https://launchpad.net/ubuntu/+archivemirrors
  
positive.code: 
  # Switch to user "nvm" from now
  USER nvm
  
  # Shellcheck
  RUN cabal update
  RUN cabal install ShellCheck
  RUN ~/.cabal/bin/shellcheck --version
  RUN echo 'export PATH="~/.cabal/bin/:${PATH}"'                                >> $HOME/.bashrc
  
  # nvm
  COPY . /home/nvm/.nvm/
  
negative.code:         realpath              \
          zsh                   \
          ksh                   \
          gcc-4.8               \
          g++-4.8               \
          xz-utils              \
          build-essential       \
          bash-completion       && \
      apt-get clean
  
  # ShellCheck with Ubuntu 14.04 container workaround
  RUN wget https://storage.googleapis.com/shellcheck/shellcheck-v$SHELLCHECK_VERSION.linux.x86_64.tar.xz -O- | \
      tar xJvf - shellcheck-v$SHELLCHECK_VERSION/shellcheck          && \
      mv shellcheck-v$SHELLCHECK_VERSION/shellcheck /bin             && \
      rmdir shellcheck-v$SHELLCHECK_VERSION                          && \
      touch /tmp/libc.so.6                                           && \
      echo "alias shellcheck='LD_LIBRARY_PATH=/tmp /bin/shellcheck'" >> /etc/bash.bashrc
  RUN LD_LIBRARY_PATH=/tmp shellcheck -V
  
  # Set locale
  RUN locale-gen en_US.UTF-8
  