Type-safe bindings for Node.js with Rust and WebAssembly

Calling Rust from TypeScript via WebAssembly means crossing a type boundary that neither language makes easy. I walked through the real friction points — string conversion, Rust-to-JavaScript data type mapping, and the serialization overhead most tutorials ignore.

The code examples progressed from raw wasm-bindgen FFI, through serde-wasm-bindgen for automatic serialization, to tsify for generating TypeScript definitions directly from Rust types.