> most notably the Microsoft one.
My bad. However it was closed source too, and abandoned rather quickly.
> True but WASM hadn't had much of a life so far, so we will see.
It uses the same security model as JS, which is much more mature than VMs not designed for so much exposure to random third party code.
> from what I see I think it's ugly as well
Ugly but not slow. WASM memory can be read and written directly from/to a typed array, instead of converting strings. Since it's fast enough, one can make less ugly APIs wrapping that behaviour.
> Java was designed with a sandbox and a bytecode verifier from very early on.
They probably protected the code itself from escaping the sandbox, but not the environment (all the API in its complex glory). WASM on the other side is exclusively allowed to talk with JS (for now, at least), therefore the only API level bugs are in JS, not in WASM.
