Requirements:
If you're on OSX you're probably best off using Homebrew to install this stuff:
$ brew install node mongodb
Usage:
$ npm install express mongoq
$ node backend.js
I've also attached a sample frontend code for using the backend via Backbone
I highly recommend the Postman Chrome extension for experimenting with REST APIs in which case you can import the attached collection export.
Truth be told so far my apps haven't been large enough to require an asset loading strategy. Usually a minified and gzipped collection of scripts is much less than one image on a page so I don't think the optimization is required until your app is huge