A Responsive Email Framework from ZURB. Quickly create responsive HTML emails that work on any device & client. Even Outlook.

Sixpack is a language-agnostic ab testing framework
Sixpack makes it easy to run A/B tests across multiple web services written in different languages.
It includes a beautiful dashboard for viewing test results and choosing winners.

Ink is a set of tools for quick development of web interfaces.

A lightweight and modular front-end framework
for developing fast and powerful web interfaces.

A set of small, responsive CSS modules that you can use in every web project.

Phalcon is a web framework implemented as a C extension offering high performance and lower resource consumption.

JavaScript Application Framework

Python SQL injection framework

Flask is a microframework for Python based on Werkzeug, Jinja 2 and good intentions. And before you ask: It's BSD licensed!

Mobello is high performance javascript UI framework for HTML5 mobile app

Superheroic JavaScript MVC Framework

A JavaScript framework for creating ambitious web applications

Build Desktop Applications for Linux, Mac and Windows using HTML, CSS and Javascript

web.go is the simplest way to write web applications in the Go programming language. It's ideal for writing simple, performant backend web services.

Meteor is an ultra-simple environment for building modern websites.

An easy to use, powerful, and flexible framework for building prototypes and production code on any kind of device.

Pyramid is a very general open source Python web framework.

Build responsive, mobile-first projects on the web with the world's most popular front-end component library.

Bootstrap is an open source toolkit for developing with HTML, CSS, and JS. Quickly prototype your ideas or build your entire app with our Sass variables and mixins, responsive grid system, extensive prebuilt components, and powerful plugins built on jQuery.

The chromeless project is an experiment into making it possible to build a web browser using only web technologies, like HTML, JavaScript, and CSS.

Backbone.js gives structure to web applications by providing models with key-value binding and custom events, collections with a rich API of enumerable functions, views with declarative event handling, and connects it all to your existing API over a RESTful JSON interface.