Edge Use Cases

Good Use Cases

1. Personalization: Geo-based content, A/B testing.
2. Redirects: Fast redirects based on cookies or headers.
3. Simple APIs: Lightweight endpoints that don't need node APIs.
4. Proxy: By default, proxy runs on the Node.js runtime in Next.js 16, with an option to use the Edge runtime.

Example: Geo-Based Content

typescript
export const runtime = 'edge';

export async function GET(request: Request) {
  const country = request.headers.get('x-vercel-ip-country') || 'US';
  
  const content = {
    US: 'Hello, America!',
    UK: 'Hello, United Kingdom!',
    DE: 'Hallo, Deutschland!',
  };

  return Response.json({
    message: content[country] || 'Hello, World!',
    country,
  });
}

When NOT to Use Edge

• Database connections (use serverless functions instead).
• Heavy computation.
• File system access.
• Native Node modules.