See the changes here: https://github.com/mikem23/koji-playground/compare/post-commit-callback

I was able to test them with a modified version of the patch for Fedora's fedmsg plugin and it works well: https://pagure.io/releng/issue/109

This would be very nice to have.

It seems like the addition of a postCommit callback could be merged without having to coordinate with other plugin authors. They (meaning me) could adjust their plugins to take advantage of postCommit at their leisure -- nothing should break if they update without being aware of the new capability.