Coffeescript
jsfiddle.net
Test your JavaScript, CSS, HTML or CoffeeScript online with JSFiddle code editor.
1,827 
$ 7,809,480.00
repl.it
Powerful and simple online compiler, IDE, interpreter, and REPL. Code, compile, and run code in 30+ programming languages: Clojure, Haskell, Kotlin (beta), QBasic, Forth,...
8,729 $ 1,634,040.00
codewars.com
Codewars is where developers achieve code mastery through challenge. Train on kata in the dojo and reach your highest potential.
25,455 $ 527,760.00
gulpjs.com.cn
Gulp.js 是一个自动化构建工具，开发者可以使用它在项目开发过程中自动执行常见任务。Gulp.js 是基于 Node.js 构建的，利用 Node.js 流的威力，你可以快速构建项目并减少频繁的 IO 操作。Gulp.js 源文件和你用来定义任务的 Gulp 文件都是通过 JavaScript（或者 CoffeeScript ）源码来实现的。
67,122 $ 200,160.00
koala-app.com
Koala is a gui for Less, Sass, Compass and CoffeeScript. Koala can run in windows, mac, and linux.
309,462 $ 26,460.00
codacy.com
Codacy automates code reviews and monitors code quality over time. Static analysis, code coverage and metrics for Ruby, JavaScript, PHP, Scala, Java, Python, CoffeeScript and CSS.
142,298 $ 78,000.00
wikitechy.com
Wikitechy a community of Developers and IT Professional,Tutorialspoint,Learn to Code to teach people how to different technologies by way of clear and organized lessons
79,132 $ 169,920.00