anchor.diff:  
   VOLUME /var/lib/mysql
   
  -COPY run.sh /
   ENTRYPOINT ["/run.sh"]
   
   EXPOSE 3306
  
positive.code: 	&& rm -rf /var/lib/mysql && mkdir -p /var/lib/mysql /var/run/mysqld \
  	&& chown -R mysql:mysql /var/lib/mysql /var/run/mysqld \
  # ensure that /var/run/mysqld (used for socket and lock files) is writable regardless of the UID our mysqld instance ends up having at runtime
  	&& chmod 777 /var/run/mysqld
  
  # comment out a few problematic configuration values
  # don't reverse lookup hostnames, they are usually another container
  RUN sed -Ei 's/^(bind-address|log)/#&/' /etc/mysql/my.cnf \
  
negative.code: 
  # add our user and group first to make sure their IDs get assigned consistently, regardless of whatever dependencies get added
  RUN groupadd -r mysql && useradd -r -g mysql mysql
  
  COPY run.sh /
  
  # add gosu for easy step-down from root
  ENV GOSU_VERSION 1.7
  