How can we optimize Edge Functions with Node.js 24 HTTP/3 to solve 100s timeouts on Vercel in global traffic spikes?

Node.js 24 with HTTP/3 support on Vercel Edge Functions cuts connection overhead and boosts throughput during global spikes, solving 100s timeouts by enabling QUIC protocol for faster handshakes and multiplexing—up to 3x better performance under load.​

Switch your Vercel Edge Functions to Node.js 24 runtime (now default in Next.js 16) and enable HTTP/3 via runtime: 'edge' with preferredRegion for regional pinning near your data sources. This leverages QUIC for lower latency handshakes (0-RTT), better multiplexing, and congestion control, preventing timeouts during traffic surges by reducing TTFB from 100s to sub-50ms globally. Add aggressive caching, streaming responses, and maxDuration: 300 to handle long-running requests while Vercel's Fluid Compute auto-scales concurrency. Monitor via Vercel Analytics to fine-tune regions and avoid cold starts.​

Code

// app/api/heavy-task/route.ts
export const runtime = 'edge';
export const preferredRegion = ['iad1', 'sin1'];
export const maxDuration = 300;

export async function GET() {
  const encoder = new TextEncoder();

  const stream = new ReadableStream({
	async start(controller) {
  	for (let i = 0; i < 100; i++) {
    	await new Promise((r) => setTimeout(r, 100));
    	controller.enqueue(encoder.encode(`Chunk ${i}\n`));
  	}
  	controller.close();
	},
  });

  return new Response(stream, {
	headers: {
  	'Cache-Control': 's-maxage=60, stale-while-revalidate',
  	'Content-Type': 'text/plain',
	},
  });
}