Deku - Functional view library for building UI components as an alternative to React
Browsersync - Browsersync makes your tweaking and testing faster by synchronising file changes and interactions...
Preact.js - Preact is a fast 3kB alternative to React with the same modern API. Components & Virtual DOM.
CodeKit - CodeKit allows you to optimize the performance of your website by automatically and efficiently compiling a variety of popular languages.
w2ui - W2UI is a small JavaScript UI library with a complete set of widgets: layout, grid, sidebar, toolbar, tabs, fields, popup, utilities.
Ghostlab - Ghostlab allows you to test out a newly developed website on a variety of browsers and mobile devices at the same time. To get started, simply drag the web address to the Ghostlab system and press the play button. Read more about Ghostlab.