[pornel]

The Rust version is longer mostly due to boilerplate for WASM<>JS interface, and awful vertically-exploded formatting (probably caused by rustfmt's dumb heuristics).

but the core loop in Rust is pretty straightforward. It could have been shortened and optimized further.

Also keep in mind that the larger the project, the harder it gets to keep JS in the performance sweet spot without tipping over any JIT heuristic, using GC, or accidentally causing a perf cliff, while the Rust has pretty stable and deterministic optimizations and keeps its memory management control at any scale.