Pegasus
Load data while still loading other scripts and display data faster in jQuery, Backbone, Angular, ... apps
Invisible
Invisible.js: Reusable models for the client and the server
Venus.js
where bugs go to die
Serenade.js
Client side MVC framework
Mediator.js
An implementation of the mediator pattern for asynchronous events in Javascript
Cellx
Ultra-fast implementation of reactivity for javascript
Terrificjs
Terrific JavaScript Framework
Then.js
The fastest, smallest, fully compatible, full-featured asynchronous module!
Query Loader2
Version of the QueryLoader by Gaya Design. Preload images with ease.
Nanobar
Very lightweight progress bars. No jQuery
Delorean
An Agnostic, Complete Flux Architecture Framework
Backbone Nested
A plugin to make Backbone.js keep track of nested attributes.
Pilot
Pilot — multifunction JavaScript router.
Thinkjs
Use full ES2015+ features to develop Node.js applications, Support TypeScript.
Knockout
Knockout makes it easier to create rich, responsive UIs with JavaScript
Intercooler Js
Making AJAX as easy as anchor tags
Handlebars Helpers
A small collection of useful helpers for Handlebars.js