The container config is in git: https://github.internet2.edu/docker/grouper
Each commit will kick off a build, so do NOT push to existing branches which are released
Jenkins is here: https://jenkins.testbed.tier.internet2.edu/
Here is an example of a job: https://jenkins.testbed.tier.internet2.edu/job/docker/job/grouper/job/2.5.25/
After making a Grouper release (tag in git), release in sonatype.
Then make a new branch in docker/grouper (2.5.x). Change the Dockerfile in two places with new version, and commit and push the branch