Butterfly is designed to help developers focus on being productive, instead of spending time (and money) looking for different libraries to fit their needs. The core library provides an AMD engine to build SPA websites, MVC support to help you organize your code, abstract caching layer for extra performance, responsive layout support for supporting mobile and tablets, huge set of UI controls, and many extra features you'll learn as you progress.

The suggested installation option is using Bower:

bower install butterflyjs

For those who like to setup stuff manually, feel free to download the latest version directly from github or the webpage using the following links:

https://github.com/buttterflyframework/butterfly/releases/

http://butterflyjs.com/

The MIT License (MIT)

Copyright (c) 2014, Semir Babajić

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.