I wrote a compiler for the Pinky Scripting language that does code generation targeting wasm. It's written in TypeScript with the webassembly bytecodes mapped out to helper functions like i32.const(0)

The url is to a playground where you can write code in the Pinky Scripting Language and see the tokens, ast, bytecode, and output. Pinky Lang has a straight-forward grammar and is designed to be used for learning about compilers.