I see you're using wasm_bindgen quite a bit, but from a cursory look at the code; I can't figure out something:
I can see how you're using wasm in the front-end, but could you please elaborate a bit more about in the backend? I presume that your backend is Rust based?
I spent last weekend porting some code from NodeJS to a wasm module. I got it sort of working on Node, but haven't tried it on the browser yet (ran out of weekend).
I'm quite optimistic about wasm [and Rust with wasm_bindgen]. I'd been thinking of writing a native add-on for Node, but the idea that I can use wasm instead is exciting.