Cant belive your project of making a game a week was 8 years ago. it was such a nice project! Over the years lessmilk stuck in my mind as a example of a very cool project that also made some money.
I also dont get the point of Deno. when i was looking into it seemed to me that was presented as a modern NPM alternative. Yet, it is completely unusable for any kind of frontend work. Which is wierd, since javascript is a frontend language. You cannot use it to write anything that uses DOM API. Not sure if that is supposed to change. Would be nice if it was clearer that it is a solution for back-end only.
I think this is a very interesting case study of a solo developer making money in free software.
on the official website https://vital.audio/ there are several premium tiers. These premium tiers are (as far as I understand) still compatible with 'free software' ideas (additional sound presets, skins, etc.).
This synth is already popular around the whole music community. Functionality easily rivals other synth software sold for $200+.