Lightrail is a minimalist Rails 3 stack for apps that serve primarily APIs, with a particular focus on JSON APIs. This makes Lightrail an ideal Rails backend for client-heavy HTML5/JS applications, particularly single-page applications written in frameworks like Backbone.js, Ember.js, and Spine.

General ruby templating with json, bson, xml, plist and msgpack support

It works by sending and receiving small bits of JSON via UDP using an efficient routing system based on Kademlia, a proven and popular Distributed Hash Table. Everything within TeleHash is routed based on a generic SHA hash of the related id or URL.

Objectify is a new Mac® application for Objective-C developers that dramatically speeds the everyday process of creating Cocoa class implementations based on JSON content.