Website Grader - Grade your website's strengths and weaknesses in seconds.
CodeKit - CodeKit allows you to optimize the performance of your website by automatically and efficiently compiling a variety of popular languages.
WebSite Auditor - The techie's SEO spider: find site issues other tools miss
Prepros - Compile Less, Sass, Scss, Stylus, Jade, Coffeescript, Haml and Markdown with live browser refresh.
PageSpeed Ninja - One-click page speed boost for WordPress
Live.js - Live. js. one script closer to designing in the browser. Say goodbye to Alt-Tab. Live.