Of course you're required to have a WASM runtime to run WASM bytecode. How else could it run? It's no different to a JVM or .NET in that regard. JVM bytecode i

Of course you're required to have a WASM runtime to run WASM bytecode. How else could it run? It's no different to a JVM or .NET in that regard. JVM bytecode is open, standardized and quite easy to implement. CLR bytecode likewise albeit less easy to implement. You can implement a simple JVM on your own. Avian is an example of a lightweight JVM written by two guys (albeit very productive guys) and that didn't only implement the spec but had a proper JIT compiler, AOT compiler and semi-decent garbage collector too! In practice, ease of implementation isn't very important for this sort of thing. Having a good open source implementation is sufficient. WASM has this in V8 and other than the rewrite-it-in-rust factor it's not super clear (to me?) what other runtimes bring to the table? > Because of this simplicity it is also an easy target to compile to No, this is backwards. WASM's simplicity makes it harder to compile to, not easier, because language implementations have to do more themselves. That's why even after many years the only languages people are using with it are languages with very minimal demands on the runtime, like C or Rust. Languages with more advanced compilation requirements like GC integration (modern GC algos affect the compiler too) have been ignoring WASM so far, and this is why V8's JavaScript engine isn't itself running on WASM.