Skill: next-v16

Next.js 16 App Router (GA October 2025). Prefer the version-matched docs in node_modules/next/dist/docs/ over training data. Codemods: npx @next/codemod@canary upgrade latest, middleware-to-proxy, next-async-request-api.

Scope

• Applies to: Next.js 16 App Router — Turbopack, Cache Components vs previous cache model, proxy.ts, async request APIs, Server Components, Server Actions, streaming, metadata, client islands
• Does NOT cover: Pages Router, generic React 19 (see vercel-react-v1), non-Next server rendering

Assumptions

• Next.js 16.x, React 19.2 App Router, Node.js 20.9+, TypeScript 5.1+
• Two cache models exist. Detect cacheComponents in next.config before choosing APIs
• fetch is not cached by default in either model. Opt in explicitly

Principles