SharedArrayBuffer gives you a byte array, and asks you to re-implement the entire JavaScript universe on top of that. String -> use TextEncoder to copy in / out of a byte buffer. Object/class? Sure, devise your own protocol to serialize + copy instances in/out of a byte array. Even basic arithmetic operations on a TypedArray over a SharedArrayBuffer is slow AF in v8 compared to a "native" JS Array<number> for small-medium integers, because our current JIT compilers can jit the fuck out of regular arrays but struggle with TypedArray stuff. It's so sad.