On March 11, Microsoft announced that it would port the TypeScript compiler and toolset, which are currently written in TypeScript itself, to Go to greatly improve performance and the developer experience.
The current TypeScript compiler, tsc, runs on Node.js, so it needs a JavaScript runtime, and that has sometimes caused slowdowns in large projects.
With this native Go port, however, tsc will be able to run directly on the operating system without a separate runtime environment.
Although it is still in the early stages of development, Microsoft said this could cut tsc run times on large codebases by 10x or more.

Comparison of TypeScript run times for each codebase

TypeScript, currently at version 5, plans to introduce deprecations and changes to some features for the native transition in the next version, 6, and to release the Go-based native compiler as TypeScript 7 once it reaches feature parity.
Microsoft also said its long-term goal is to let developers choose between the JavaScript-based version and the native version as needed.

A 10x Faster TypeScript