anchor.diff:  
   USER ${user}
   
  -RUN mkdir -p "${JENKINS_HOME}"
   COPY jenkins-support /usr/local/bin/jenkins-support
   COPY jenkins.sh /usr/local/bin/jenkins.sh
   ENTRYPOINT ["/bin/tini", "--", "/usr/local/bin/jenkins.sh"]
  
positive.code: RUN chmod 400 ${JENKINS_USER_HOME}/.ssh/id_rsa
  
  RUN chown -R ${user}:${user} /usr/share/jenkins/ref
  RUN mkdir -p "${JENKINS_USER_HOME}"
  RUN chown -R ${user}:${user}  "$JENKINS_USER_HOME"
  
  # for main web interface:
  EXPOSE 8080
  
negative.code: # ensure you use the same uid
  RUN groupadd -g ${gid} ${group} \
      && useradd -d "$JENKINS_USER_HOME" -u ${uid} -g ${gid} -m -s /bin/bash ${user}
  
  # `/usr/share/jenkins/ref/` contains all reference configuration we want 
  # to set on a fresh new installation. Use it to bundle additional plugins 
  