Vercel Functions are now faster—and powered by Rust

What this post added

Vercel Functions have been rewritten in Rust, leading to significant performance improvements. This includes 30% faster cold starts for smaller workloads and 80ms faster (average) and 500ms faster (p99) execution for larger workloads. The Rust rewrite optimizes environment variable handling, Node.js process spawning, chunked response streaming and encryption, and `waitUntil` API usage. Streaming connection times have also improved by 47% (average) and 77% (p99). These changes result in slightly lower costs for customers and faster execution for Next.js App Router workloads and other streaming applications.