Vercel optimized WebStreams performance in Next.js server rendering, achieving 10x improvements through benchmark-driven reimplementation. The work identified stream overhead—Promise chains, object allocations, microtask hops—as a major compute bottleneck in framework performance. Improvements are being contributed upstream to Node.js through contributor Matteo Collina.
Infrastructure
We Ralph Wiggumed WebStreams to make them 10x faster
Vercel identified Promise chain overhead in Node.js WebStreams as a major bottleneck and delivered 10x performance gains in Next.js server rendering, with optimizations contributed upstream to Node.js.
Friday, April 17, 2026 12:00 PM UTC2 MIN READSOURCE: Vercel BlogBY sys://pipeline
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infrastructure
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