Does this support writing audio sample processing code in JavaScript? From the examples it looks like JavaScript code connects together pre-existing audio processing nodes, but it's unclear if you can write your own nodes in JavaScript.

Also, the use of the term "pure function" confused me. Pure functions have no side-effects (https://en.wikipedia.org/wiki/Pure_function). Why is this necessary? It seems like non-pure functions could generate the graph of nodes too, so restricting ourselves to pure functions seems like a limitation. Or does the term "pure function" actually mean "in functional programming style" (i.e. functions, not objects) in this blog post?