vibe.d with explicit threads/threadpool instead of fibers

[Arun Chandrasekaran via Digitalmars-d-learn]

I am looking for a RESTful framework in D, which can interact 
with an existing backend processes (C++) via ZeroMQ and shared 
memory. I thought vibe.d might be a viable option. But I 
discussed with someone on Freenode #d and found that vibe.d 
doesn't support explicit threading [1].

Can someone confirm the behaviour?
Is it not possible to allocate a bunch of threads or a threadpool 
for vibe.d to work with?

PS: We have this working already with C++ only solution where the 
frontend communication happens on protobuf over ZeroMQ. I'm just 
trying to migrate it to RESTful interface.

[1] http://pastebin.com/cAw2yaYg