Spine
Lightweight MVC library for building JavaScript applications
Mjml
MJML: the only framework that makes responsive-email easy
Alertify.js
JavaScript Alert/Notification System
Simplate
A simple, but powerful, templating engine for JavaScript.
Cram
Simple AMD and CommonJS module bundler.
Eve.js
A <3kb JavaScript file providing three simple methods to organize code into CSS namespaces which magically restrict code to the current context, allowing for dramatic reductions to code size and development time.
Nunjucks
A jinja2-inspired templating system for javascript
Stapes
a (really) tiny Javascript MVC microframework
JavascriptMVC
Develop with direction! With CanJS, jQuery++, FuncUnit, Steal, DocumentJS.
Hermes.js
Message and Error logger implementation
Hamsters.js
100% Vanilla Javascript Multithreading & Parallel Execution Library
LABjs
Loading And Blocking JavaScript: On-demand parallel loader for JavaScript with execution order dependencies
Kefir
A Reactive Programming library for JavaScript
Script.js
Asyncronous JavaScript loader and dependency manager
Overmind
Overmind - Frictionless state management
Webix
Stable releases of Webix UI - JavaScript library for building mobile and desktop web apps
Optics
Profunctor implementation of Lenses, Prisms, Traversals, Isos, etc.