No no no, wasm has shitty speed if you want to emulate something (it doesn't even support JIT), the problem is in its architecture (tons of restrictions like no self modifying code, no jumps).. this can't be fixed, we need something real, something like WebKVM.
On the web you can dynamically create new Wasm modules and use JS APIs to load them, though there are ergonomic issues. There are per-module costs and systems like CheerpJ and CheerpX currently do batching of multiple functions into a module to mitigate the per-module costs.
