DropBox developers Dan W, Ziga M and Chris V explain their choice in a blog post, offering brevity of syntax as their main concern and citing the following statistics from the company's re-coding project as evidence of CoffeeScript's lesser burden for developers.
|Lines of code||23437||18417|
That 5000 fewer lines of code, the developers write, “is beneficial for simple reasons — being able to fit more code into a single editor screen, for example.”
“Measuring reduction in code complexity is of course much harder,” the coders add, “but we think the stats above, especially token count, are a good first-order approximation.”
Indeed, while the developers feel more productive, there's no indication the site works better after the transition to the new scripting language. “The size of the compressed bundle didn’t change significantly pre- and post-coffee transformation, so our users shouldn’t notice anything different,” the trio write. “The site performs and behaves as before.”
There's nothing new, of course, about software re-platforming projects. Here in El Reg's antipodean eyrie we've covered (in past lives) a few aimed at extending the life of applications written in legacy languages. Those projects, however, had a commercial outcome as their rationale. It's unclear if that's the case here. ®