I don't think that's ignorance :)

Embedding Janet in the browser is hard! My real motivation for making this website was to have a simple example to point to of how to do it. Short answer: Emscripten + WebAssembly. Long answer: https://github.com/ianthehenry/toodle.studio

Specifically I think these are the interesting bits:

https://github.com/ianthehenry/toodle.studio/blob/master/bui... https://github.com/ianthehenry/toodle.studio/blob/master/src...