We rewrote our Rust WASM Parser in TypeScript – and it got 3x Faster

A team rebuilt their Rust-to-WASM parser in TypeScript and achieved a 3x speed improvement. The bottleneck was not Rust's execution speed but the WASM-JS boundary overhead—serializing/deserializing data between runtimes. Eliminating the boundary entirely by rewriting in TypeScript, which runs natively in V8, removed the overhead and significantly improved streaming latency.