Have you checked out PubSubHubbub project? http://code.google.com/p/pubsubhubbub/ http://code.google.com/p/pubsubhubbub/ It looks like there's a lot of overla

Have you checked out PubSubHubbub project? http://code.google.com/p/pubsubhubbub/ http://code.google.com/p/pubsubhubbub/ It looks like there's a lot of overlap with the feature set you need, as well as the advantage of some extra documentation + testing. It's a Python WSGI app, instead of Sinatra/Rack, and the data over the wire is encoded as Atom, but there could be some useful lessons to work from at least.