Transcription
TypeScript just shipped the biggest release in its history. 1.5 million views in a single day. Here is what actually changed.
TypeScript 7 is a ground-up rewrite. The whole compiler was ported from JavaScript into Go. Same behavior, same type system, a completely new engine underneath. The payoff is raw speed, between 8 and 12 times faster on real projects.
Look at VS Code's own code base. A full type check used to take 126 seconds. On TypeScript 7, it finishes in 11. Same code, same errors, 1/10 the weight. And memory drops, too, by up to a quarter.
Three things drive it. A native Go binary instead of JavaScript, parallel type checking that spreads across your CPU cores, tunable with a new checkers flag. And a watch mode rebuilt from scratch.
Your editor feels it the most. In VS Code, the first error on a big project dropped from 17 seconds to under 1 and 1/2. Language server crashes fell by more than 60%.
The teams already on it are loud about it. Slack cut CI type checking from 7 and 1/2 minutes to just over 1. Canva went from 58 seconds to under 5. Microsoft says it saves 400 build hours a month.
Migrating is almost nothing. It is still the same TSC. You still run npm install TypeScript. The catch. Strict mode is on by default now. A few old options are gone, and editor plugins for Vue, Svelte, and Angular are not ready yet.
So, here is the real question. A 10 times faster compiler. Are you upgrading day one or waiting for your whole tool chain to catch up? Tell me below.