Principal product manager Daniel Rosenwasser reports that TypeScript 7 is now generally available – a big release, since this is the first to have the native port of the TypeScript compiler built in Go. Rosenwasser claims “speedups between 8x and 12x on full builds.”

There is a snag. Although TypeScript 7 is production-ready, it has no API; that will not come until TypeScript 7.1. It may come as a surprise to you that TypeScript has an API; it is not something highlighted in the TypeScript docs. You will find it covered in the official Wiki where there is an article on using the compiler API dated October 2023 and advising that “this is not yet a stable API.”

Despite the compiler API being somewhat obscure, Rosenwasser says this means that “workflows that use Vue, MDX, Astro, Svelte, and others will likely not yet be able to leverage TypeScript 7. Similarly, specialized type-checking within templates like Angular will also likely not use TypeScript 7.” That is a significant blocker to adoption.

Users of Visual Studio Code should install the dedicated TypeScript 7.0 extension which already has enthusiastic reviews. “Saves us lots of time in CI/CD. The difference in speed is huge!” said one.

Personally I now use TypeScript rather than JavaScript almost exclusively, when targeting browser scripting, and will endeavour to switch to 7.0 immediately. I would much rather have the compiler find errors, than have them turn up in production.