Benjamin Lesné retweetledi
TypeScript 6.0 shipped March 23, 2026.
It's the last version of the TypeScript compiler written in TypeScript.
Everything after it — TypeScript 7.0 — is rebuilt in Go. 🐳
The numbers:
→ VS Code (1.5M lines): 77 seconds → 7.5 seconds
→ Sentry codebase: 133 seconds → 16 seconds
→ Memory usage: cut in half
That's not a small improvement. That's a different category of tool.
But first — TypeScript 6.0 is the bridge release you need to get through. Here's what changed:
🔧 9 new defaults: strict ON, ESM as default, bundler module resolution, all files treated as modules
❌ Breaking changes: ES5 target removed, AMD/UMD deprecated, --outFile gone, @types no longer auto-discovered
✅ New features:
- Temporal API types (proper date handling, finally)
- RegExp.escape() and Promise.try() types
- Map.getOrInsert() typed correctly
- #/ subpath imports
- Improved method type inference
💡 The Go compiler (tsgo) is already available:
npm install @typescript/tsgo
tsgo --project tsconfig.json
Try it. The compile time difference is immediate and shocking.
I wrote the full guide for what changed, what broke, how to upgrade, and what TypeScript 7.0 actually means for your CI/CD and monorepo workflows.
Is your team already planning the 6.0 upgrade? 👇
#TypeScript #JavaScript #WebDev #Frontend #NodeJS #100DaysOfBlogging medium.com/p/typescript-6…
English
