Yes, what I call "embeddable Docker" is a desirable thing. It will help Docker integrate with other centralized daemons that want to own the process tree, like systemd. I've made it very clear in the past that I want this too, but would welcome help to implement it. I'm actually putting together a "hacking sprint" so that the various interested parties can participate in making it happen. I actually offered the CoreOS guys to join the effort last week - but they seem determined to do it themselves instead. That's OK but they should know they are welcome back if they change their minds.

So, anybody want to help hack on embedded Docker?

See also this good, unbiased explanation of the relationship between Docker, CoreOS and systemd: http://www.ibuildthecloud.com/blog/2014/12/03/is-docker-fund...