Notice that CoffeeScript can be used organically with many other mainstream frameworks and technologies. For example in Ruby on Rails support was included starting from version 3.1.
In COAX Software we have a good history with CoffeeScript on our projects. Every our developer is skilled enough to build any complex functionality utilizing this language.
And in conclusion a killer fact:
CoffeeScript is being preferred by many titans of the market like GitHub and Dropbox.
Best quick guide to start working with us.