I think you are misunderstanding; robotjs is written in C but it is a module for Node.js which means you implement it using Javascript.

Node.js modules can be written in C or Javascript but implementing new features like this requires you to use C so there is no "making this available for other languages".

Well, you could take the API it presents and fit it to another language's FFI. Maybe someone who wants it for their language will do that.

I stand corrected. I looked closer.

I never knew node modules could be written in C.

I was searching around for a js wrapper, but found that even the JS API was implemented in C [1].

I would only implement the low level "hardware" primitives in C, then implement the high level API in JS like Chromium's Blink-in-JS initiative [2]. Once they start expanding the high level functionality, they will lose potential contributors by sticking with pure C.

[1] https://github.com/octalmage/robotjs/blob/master/src/robotjs...

[2] http://www.chromium.org/blink/blink-in-js

You'd be surprised by how many C/C++ programmers there are out there! I've already been surprised by the number of contributions. But yeah, using C wasn't a choice, it was the only option. Luckily we already have all planned features implemented in C.