Why Next.js for AI?

Next.js provides the perfect foundation for AI apps: server-side rendering for SEO, API routes for backend logic, and streaming support for real-time responses.

Setting Up

  • Install the Vercel AI SDK: `npm install ai @ai-sdk/openai`
  • Create an API route at `app/api/chat/route.ts`
  • Use the `streamText` helper for real-time token streaming.

Core Patterns

### Streaming Chat

Use the `useChat` hook on the client side. It handles streaming, message state, and abort automatically.

### RAG Integration

  • Store documents in a vector database (Pinecone, Qdrant, or pgvector).
  • On user query, retrieve relevant chunks.
  • Include chunks in the system prompt as context.

### Image Generation

  • Use DALL-E or Stable Diffusion APIs.
  • Display loading states with optimistic UI updates.

Performance Tips

  • Edge Runtime: Deploy API routes to the edge for lower latency.
  • Caching: Cache embeddings and common responses.
  • Batching: Group multiple API calls when possible.

Deployment

  • Deploy on Vercel for automatic edge deployment.
  • Use environment variables for API keys.
  • Set up rate limiting to control costs.

Streaming Responses

The Vercel AI SDK provides excellent streaming support. Use `useChat` hook for chat interfaces and `streamText` on the server for efficient token-by-token delivery. Always show a loading indicator and allow users to stop generation mid-stream.

State Management

  • Conversation history: Store in database (PostgreSQL recommended) with proper indexing on conversation_id and created_at.
  • Optimistic updates: Show user messages immediately, then reconcile with actual AI response.
  • Caching: Cache completed conversations to reduce API costs. Use Redis for session-level caching.

Performance Tips

  • Edge runtime: Deploy API routes on Vercel Edge or Cloudflare Workers for lower latency.
  • Parallel tool calls: When using function calling, execute independent tools in parallel.
  • Image optimization: Use Next.js Image component with proper sizing. AI-generated images should be compressed before display.
  • Rate limiting: Implement per-user rate limiting to prevent abuse and control costs.