Request latency (p50):
  Cloudflare Workers:  2ms   ← Edge speed
  Vercel Edge:         5ms
  AWS Lambda (Node):   45ms  (warm)
  AWS Lambda (Node):   350ms (cold start)
  AWS Lambda (Java):   2500ms (cold start!)

typescript
// Cloudflare Worker — runs at 300+ locations globally
export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const country = request.cf?.country;
    
    // Route to nearest backend
    const backend = country === 'IN' 
      ? 'https://api-mumbai.myapp.com'
      : 'https://api-virginia.myapp.com';
    
    const response = await fetch(backend + new URL(request.url).pathname);
    
    // Cache at edge
    const cached = new Response(response.body, response);
    cached.headers.set('Cache-Control', 's-maxage=60');
    
    return cached;
  }
};

typescript
// Next.js Middleware (runs on Vercel Edge)
import { NextResponse } from 'next/server';
import type { NextRequest } from 'next/server';

export function middleware(request: NextRequest) {
  const token = request.cookies.get('auth_token');
  
  if (!token && request.nextUrl.pathname.startsWith('/dashboard')) {
    return NextResponse.redirect(new URL('/login', request.url));
  }
  
  // Add geo headers
  const response = NextResponse.next();
  response.headers.set('x-user-country', request.geo?.country || 'unknown');
  return response;
}

Traditional:
  User → CDN → Server (US-East) → Database
  Latency: 200-500ms globally

Edge-First:
  User → Edge (nearest PoP) → Database (global)
  Latency: 20-50ms globally