#build

TypeScript in Go, Vite on Rolldown, Biome instead of ESLint and Prettier, uv on the Python side. In eighteen months most of the tools that used to be written in the language they process were replaced by native ones. I moved a monorepo across all of them. Here is the before and after, and the two places where the rewrite is not a free win.

The Go port of the TypeScript compiler went GA on 8 July 2026 with an 8x to 12x speedup on full builds. I moved a six package pnpm monorepo across in an afternoon. This is what actually changed, what broke, and the one thing I would check before you run the upgrade.