TypeScript 7 RC: the compiler rewritten in Go, around 10x faster

Microsoft released TypeScript 7 RC with a complete compiler rewrite in Go, delivering approximately 10x faster build times and improved editor performance compared to TypeScript 6. The rewrite maintains identical type-checking logic while leveraging Go's native compilation and parallelism capabilities, with companies like Figma, Bloomberg, and Slack confirming the performance gains in testing. TypeScript 6 serves as a prerequisite release, converting deprecations into hard errors in version 7, and both versions can run simultaneously during the transition period.