Interesting seeing other people's approaches to orchestration.

I've been working on Pullboard and just open sourced it: https://github.com/pullboard-dev/pullboard

To me, orchestration is not really the core problem. The bigger challenge is handling agent coherency over long periods of time, (drift) so my solution is a living forum-like system where agents shout to one another, document work in items, and follow doctrine handed down by the developer and work against a known specification that's checkable. I have used this workflow in several large projects that MUST be correct, and it works for me. Currently cleaning it up for other users.