Montage
Core framework: Montage simplifies the development of rich HTML5 applications by providing modular components, real-time two-way data binding, CommonJS dependency management, and many more conveniences. Join us on irc.freenode.net#montage or https://groups.google.com/d/forum/montagejs
Layzr.js
A small, fast, modern, and dependency-free library for lazy loading.
Bottlejs
A powerful, extensible dependency injection micro container for JavaScript applications
Oraclejet
Oracle JET is a modular JavaScript Extension Toolkit for developers working on client-side applications.
Lovli.js
A boilerplate for developing react+redux applications with rethinkdb/horizon as realtime database and express for the server.
Q
A tool for making and composing asynchronous promises in JavaScript
Backbone Layout Manager
A layout and template manager for Backbone.js applications.
Alertify.js
JavaScript Alert/Notification System
Hogan.js
A compiler for the Mustache templating language
Cloudinary Js
Cloudinary JavaScript library
Chaplin
An Application Architecture Using Backbone.js
Jsblocks
Better MV-ish Framework
Inferno
An extremely fast, React-like JavaScript library for building modern user interfaces
Postal.js
JavaScript pub/sub library supporting some advanced subscription features, plus message capture and replay
Vue
Intuitive, fast & composable MVVM for building interactive interfaces.
Grips
Simple-logic templates
Is.js
Micro check library