Mastering Next.js 16: App Router, Server Components & Performance

Mastering Next.js App Router

What's New in Next.js 16? - Turbopack for faster builds - Improved Server Components - Enhanced API routes - Better error handling

App Router Basics The App Router provides file-based routing in the `app/` directory:

app/
├── page.tsx           # Home page
├── about/
│   └── page.tsx      # /about
├── blog/
│   └── [slug]/
│       └── page.tsx  # /blog/[slug]
└── layout.tsx        # Root layout

Server vs Client Components - Server Components: Data fetching, sensitive operations - Client Components: User interactions, animations - Mix and match for optimal performance

Data Fetching Strategies 1. **Direct Database Access**: Server components can query databases directly 2. **API Routes**: RESTful endpoints for client-side fetching 3. **API Middleware**: Authentication, logging, rate limiting

Performance Optimization - Image optimization with next/image - Script optimization - Code splitting and lazy loading - Static generation vs ISR vs SSR

SEO Best Practices - Meta tags with generateMetadata - Structured data (JSON-LD) - Sitemap generation - Open Graph tags