🔄 Enterprise Migration Pattern

The Problem with Big-Bang Rewrites

The Incremental Approach

Middleware Proxy — Code

// middleware.ts
import { NextResponse } from 'next/server';

// Routes that have been migrated to Next.js
const migratedRoutes = [
  '/',
  '/about',
  '/pricing',
  '/blog',
  '/blog/:slug*',
];

export function middleware(request) {
  const { pathname } = request.nextUrl;
  
  // If route is migrated, let Next.js handle it
  const isMigrated = migratedRoutes.some(route => {
    const pattern = route.replace(':slug*', '.*');
    return new RegExp(`^${pattern}$`).test(pathname);
  });
  
  if (isMigrated) {
    return NextResponse.next(); // Next.js handles this route
  }
  
  // Proxy to legacy site for non-migrated routes
  return NextResponse.rewrite(
    new URL(pathname, 'https://legacy.example.com')
  );
}

// next.config.ts (alternative: rewrites in config)
// rewrites: async () => ({
//   fallback: [{
//     source: '/:path*',
//     destination: 'https://legacy.example.com/:path*'
//   }]
// })

Customer Results

🎯 SE Selling Points