anchor.diff:  
       
   # now we create a dummy account 
  +
   RUN adduser --disabled-password --gecos "" clara && adduser clara sudo && su clara
   WORKDIR /home/clara
   RUN git config --global user.name nyan && git config --global user.email nyan@pa.su
  
positive.code: 
  # finally echo this in a fancy way
  
  RUN echo "senpai it worked!"
negative.code: # Clara Dockerfile
  # Copyright 2017 (c) Clara
  # Licensed under MIT
  
  FROM ubuntu:16.04
  
  #overrides for APT cache
  
  RUN echo "force-unsafe-io" > /etc/dpkg/dpkg.cfg.d/02apt-speedup
  RUN echo "Acquire::http {No-Cache=True;};" > /etc/apt/apt.conf.d/no-cache
  
  # get dependencies
  
  RUN apt update && \
      apt -y install \
      apt-utils \ 
  