That may sound strange, but it turns out I don't use WASM as well. Last time I touched this part was ~8 month ago, and WASM was just one of the experiments, and I forgot about this. Just remember it was hard to find a right approach initially, on how to execute JS without NodeJS environment. But with a right set of polyfills it works now.

Anyway, I see we have a bit different approaches on how to handle JS part, and I could get some ideas from that.