Originally published on danholloran.me
If you've worked on a large TypeScript codebase, you know the pain. You hit save, you wait. The type-checker grinds through hundreds of files, your IDE lag spikes, and CI takes minutes just to get through tsc --noEmit. It's not TypeScript's fault — the language has always made a reasonable trade-off between expressiveness and performance. But that trade-off is about to get renegotiated.
TypeScript 7.0 is currently in beta, and the headlining change is a complete rewrite of the compiler — from TypeScript itself to Go. The result is build times that are roughly 10x faster. Not 10% faster. Ten times.
Why Go, and Why Now
The TypeScript team's choice of Go wasn't about hype — it was about constraints. The existing compiler is JavaScript running on Node.js, which means it inherits V8's garbage collector and single-threaded execution model. That's fine for small projects, but as codebases scale to hundreds of thousands of lines, GC pauses and sequential file processing become the bottleneck.
