“This set of changes (…) makes any merge to the master branch build devel packages and publish them to the new devel repository.” Source:
https://github.com/virtualmin/webmin-jailkit/pull/7
More relevant info:
https://github.com/virtualmin/webmin-jailkit/pull/10
We see some test examples here: https://software.virtualmin.com/vm/7/gpl-devel/rpm/noarch/
This is very exciting!