According to CoinMeta, renowned developer Theo open-sourced the tsc-rs project, with the aim of porting Microsoft's TypeScript compiler written in Go to Rust, replacing the compiler, type checker, and language server, with the goal of directly substituting for the official tsc. The project lasted for about five months. Initially, Theo used tools such as Codex to generate over 1.3 million lines of Rust code, but compatibility never exceeded around 84%. Converted at the current price of API, the cost involved exceeded $400,000. Later, he switched to Claude Opus 5.5 and started over with the porting process; a working prototype was created in 10 hours, and the main work was completed within two weeks, costing approximately $24,000. Tests showed that tsc-rs has passed 181,711 tests transferred from Go, with results basically consistent with Microsoft's Go version, with only a few known behavioral differences. Additionally, according to performance tests of 60 open-source projects, the type checking time for Rust version is about half that of the Go version.