Backbone.Marionette is a composite application library for Backbone.js that aims to simplify the construction of large scale JavaScript applications. It is a collection of common design and implementation patterns found in the applications that I (Derick Bailey) have been building with Backbone, and includes various pieces inspired by composite application architectures, such as Microsoft's "Prism" framework.

• Scale applications out with modular, event driven architecture
• Sensible defaults, such as using Underscore templates for view rendering
• Easy to modify to make it work with your applicaton's specific needs
• Reduce boilerplate for views, with specialized view types
• Build on a modular architecture with an Application and modules that attach to it
• Compose your application's visuals at runtime, with Region and Layout
• Nested views and layouts within visual regions
• Built-in memory management and zombie killing in views, regions and layouts
• Built-in event clean up with the EventBinder
• Event-driven architecture with the EventAggregator
• Flexible, "as-needed" architecture allowing you to pick and choose what you need
• And much, much more

This implementation of the application uses Marionette's module system. Variations using RequireJS and a more classic approach to JavaScript modules are also available here.