anchor.diff:  # 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}
  -
  -# Jenkins home directory is a volume, so configuration and build history 
  -# can be persisted and survive image upgrades
  -VOLUME /home/jenkins/jenkins_data
   
   # `/usr/share/jenkins/ref/` contains all reference configuration we want 
   # to set on a fresh new installation. Use it to bundle additional plugins 
  
positive.code: 
  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"]
  
negative.code: RUN chmod 400 ${JENKINS_USER_HOME}/.ssh/id_rsa
  
  RUN chown -R ${user}:${user} /usr/share/jenkins/ref
  RUN mkdir -p "${JENKINS_HOME}" && chown -R ${user}:${user}  "$JENKINS_HOME" && mkdir -p "${JENKINS_USER_HOME}" && chown -R ${user}:${user}  "$JENKINS_USER_HOME"
  
  # Jenkins home directory is a volume, so configuration and build history 
  # can be persisted and survive image upgrades
  VOLUME /home/jenkins/jenkins_data
  
  # for main web interface:
  EXPOSE 8080
  