YUI3
YUI is a free, open source JavaScript and CSS library for building richly interactive web applications.
Alloy Ui
Alloy is a UI metaframework that provides a consistent and simple API for building web applications across allthree levels of the browser: structure, style and behavior.
Boiler
Boiler is a utility library that makes every day tasks in JavaScript easier by providing over 115 methods that work on arrays, collections, functions, numbers, objects, and strings.
Weld
Template antimatter for Node.js (Browsers too!)
Simulacra
One-way data binding for web applications.
Inkline
Inkline is the customizable Vue.js UI/UX Library designed for creating flawless responsive websites.
RequireJS
A file and module loader for JavaScript
Oc Lazy Load
Load modules on demand (lazy load) in AngularJS
Tungstenjs
Tungsten.js is a modular framework for creating web UIs with high-performance rendering on both server and client.
Query Loader2
Version of the QueryLoader by Gaya Design. Preload images with ease.
Optics
Profunctor implementation of Lenses, Prisms, Traversals, Isos, etc.
Pilot
Pilot — multifunction JavaScript router.
Lovli.js
A boilerplate for developing react+redux applications with rethinkdb/horizon as realtime database and express for the server.
Stapes
a (really) tiny Javascript MVC microframework
PubNub
PubNub makes Real-time Real Easy with a Simple Communications API. Two Functions: Send/Receive (Publish/Subscribe). We provide a web-service API for businesses to build scalable Data Push communication apps on Mobile, Tablet and Web. Bidirectional JSON.
Knockout
Knockout makes it easier to create rich, responsive UIs with JavaScript