anchor.diff:  RUN rbenv install $ruby_version && \
       rbenv global $ruby_version
   
  +COPY --chown=ned:ned . /home/ned/src
  +
   ENTRYPOINT ["docker/entrypoint"]
  
positive.code: ENV LC_ALL C.UTF-8
  
  USER root
  
  # Update Ubuntu Software repository && update deps
  RUN apt-get update && \
  
negative.code:      libreadline-dev \
       ragel && \
       rm -rf /var/lib/apt/lists/*
  
  USER ned
  
  