(I'm responsible for the browser-side code too, and this is written in a Scheme, biwascheme, which is so much nicer than having to use Javascript, in my opinion.)
Along the way, I've created various other shell-script utilities in pForth for other purposes, which always rival the speed I'm used to getting from using AWK—mwak, specifically—which has always been impressively fast when handling large amounts of data.
Me being the only coder on this project is why I've been able to get away with indulging in this peculiar, but vastly under-appreciated, language!
This approach required a lot of courage, because I had to change a lot in my life. At some point I had to even accept that I might end up never coding again. But that proved wrong after several months of being mostly away from computer, reading books, walking, drawing, making yoga, doing all the enjoyable things that came to my mind. In my case F. Perls with his approach to living in here and now had helped me to switch to the new style of life, directed by true inner desires.
eg. I started with Basic -> QW Basic -> Pascal -> PHP -> Perl -> ruby -> golang and a lot of others languages too.
Writing code is not the hard part.
follow something like this: https://functionalcs.github.io/curriculum/
Or if you want to be something specifc follow this and find resources to learn about the topics: https://github.com/kamranahmedse/developer-roadmap
I'm one of the developers at Sublime HQ. We're all very excited about this release. If you have any questions you'd like to ask I'll do my best to answer them.