> I wonder if you have real control over the performance. In general, the mapping between CoffeeScript and JS is so trivial that it's hard to think of places w

> I wonder if you have real control over the performance. In general, the mapping between CoffeeScript and JS is so trivial that it's hard to think of places where there could be a lack of control. Of course, if that were ever an issue, CoffeeScript lets you directly embed JS by surrounding it in backticks. I also had a bad gut reaction to CoffeeScript initially, and I won't pretend it doesn't have drawbacks; the powerful, in-browser debugger that it desperately craves still hasn't yet been written, after all. But it really gets right what so many compile-to-javascript languages have gotten wrong in the past. At the very least, it is hands down the easiest way to sketch an idea for JavaScript. I just never end up feeling like I would gain anything significant by porting that sketch to native JS.