I've been really interested in Joyent's Triton implementation of the docker protocol and lx containers under SmartOS ... It actually seems like a much cleaner and more secure abstraction ironically enough (running linux under solaris, effectively). The network latency vs VM + Docker seems to be a lot better as well working better than other options like kubernetes/fabric etc.
I think my only complaint about Joyent is their storage and services seem to be quite a bit more expensive than with Azure or AWS.
I've been putting docker off cause of coreos rockt vs docker and the security problem.
Was looking for alternative such as MirageOS and unikernel.
Since it seems like Docker and CoreOS have settle their issue now I'm waiting on security.