Looking for Moneta gem rack or another server code example

I am using moneta gem for quite some time as a key\value interface for
couple storage engines.
Now I started thinking about using it as a server for couple backends.

I have started my way at:

which can be also seen at rubydoc:
http://rubydoc.info/gems/moneta/frames

There is a section about Rack Rest interface but I never figured out how
would it be used with a TokyoCabinet backend for example.
Or how would I expose couple DB backends throw one rest interface?

Thanks,
Elico