Using Chowder for Simple Rack-based authentication

I have been searching for some time for a simple rack based authentication system.

Something just complex enough.

A key requirement for me is that I'd like it to work with the data storage mechanism of my choice (which this week is MongoDb/MongoMapper).

I spotted a post on the sinatra mailing list which mentioned a fairly new contender for this sort of thing, called chowder.

It was really easy to get things going, although I found the parameters to 'use' needed to be wrapped in {} - at least when using ruby 1.8.7 - I wonder if the chowder developers are on ruby 1.9 where that kind of voodoo is acceptable..?

I've also put up a branch to a fledgling sinatra app which uses Chowder, complete with some cucumber features which test sign up and log out with a MongoDb/MongoMapper document store. That's here on the basic-chowder-features branch.