I've just pushed a project to Github which uses Action delegates in
place of interfaces.
http://github.com/markrendle/CRack
The sample code includes a console application which references a
CRack assembly, plus a Server, two handlers and a "pipe" (middleware),
all in separate assemblies. None of those assemblies reference the
CRack assembly at all; the wiring up is done entirely based on four
very complicated Action<...> signatures.
There's a README on the Github project page which has more to say.
I'd be very interested to hear people's thoughts.
Cheers,
Mark