JS ecosystem front end builds can be complex and incredibly slow these days. It's rare to see a JS app that is just written in JS and shipped as-is without some kind of long "compile" pipeline with translation to support different browsers, minifiers, CSS compilation, and tons of other cruft.

I've definitely seen JS builds be slower than medium to large size Rust builds on the same machine, especially since JS builds often involve large steps that are not parallelized. Rust parallelizes builds pretty well until the very last optimization pass and linker stage.

Go builds are impressively fast, so if that's a big pain point for you I'd look at Go frontend stuff.