I wanted to see if LLMs could port the TypeScript compiler, checker and lsp to Rust. Turns out they can.
It cost over $420,000 in tokens to do it, but you could probably have done it for ~$20k (see below)
This is an early release. It has 100% compatibility in every real world project we have tested. It should work as a drop in replacement for the vast majority of apps. See Known problems.
I used a lot of OpenAI models to try and complete this port. In total I did over $400,000 in API priced tokens with GPT-5.6 Sol and GPT 6 Astra. They wrote over 1.3m lines of Rust over multiple months of /goal loops and never got past like 84% compat.
