TypeScript 7.0 has shipped as the first stable release featuring a complete rewrite of the TypeScript compiler in Go, delivering 8x–12x build speed improvements. The rewrite was driven by performance limitations of the original JavaScript-based compiler running on V8. Benchmarks show VSCode's 2.3 million lines of code now compiles in 10.6 seconds versus 125 seconds with TypeScript 6. The team chose Go over C# or Rust for its structural similarity to JavaScript, efficient memory allocation (with the ability to disable the GC for most compilations), native cross-platform support, and strong concurrency primitives. Real-world users like Slack, who previously couldn't run full type checks locally, can now do so again.
25 Impressions