FYI,
After hearing that this might be useful to many developers, I wanted to bring to your attention the ovirt-engine master build job from patch [1] which allows you to build new rpms from an open ovirt-engine patch on Gerrit.
Its was created as temp job for a team who needed it a few months ago, but seems it might useful for other teams as well, so we decided to publish it even though its not standardized yet as part of our standard CI system.
I hope you can find it useful for your teams.