The interesting thing about the unikernel approach that we're discovering is how useful the portability of the resulting applications is. Because everything is structured as a graph of libraries, only a little modification can pull in a huge amount of useful functionality.

For instance, Martin's work on Rump+Mirage now pulls the whole safe OCaml stack into a bare metal environment: the type-safe TCP/IP, HTTP, TLS, DNS libraries can all be deployed onto any target supported by NetBSD/Rump -- which includes some pretty small embedded ARM devices that we couldn't boot on before due to the Xen requirement!

On the other side of the spectrum, Thomas Leonard has ported a good chunk of the MirageOS stack to JavaScript, and built browser applications using the Irmin Git datastructure library: http://roscidus.com/blog/blog/2015/04/28/cuekeeper-gitting-t...

We're working hard on getting all these pieces upstreamed at the moment, so it's not quite ready for primetime yet (the bare metal stack still has no network driver ported), but it's rapidly all coming together. I'm excited!