nextjs-developer

name	nextjs-developer
description	Next.js 16 App Router hub for app/ (operator :3002) — RSC, Server Actions, routing, data fetching, generateMetadata, loading/error boundaries, next/image. Use whenever building or editing page.tsx, layout.tsx, route handlers, server actions, or App Router structure. For proxy.ts, next.config.ts, Turbopack, async params/cookies, caching APIs also load references/ipix-16.md or satellite nextjs-16. For Supabase auth use ipix-supabase (references/auth/nextjs.md) — NOT archived nextjs-supabase-auth. For perf/CWV use vercel-react-best-practices (pick one primary on small tasks). NOT for CopilotKit, Mastra, or Supabase edge/migrations.
license	MIT
metadata	{"author":"https://github.com/Jeffallan","version":"2.0.0","domain":"frontend","role":"specialist","scope":"implementation"}

Next.js Developer — iPix hub

Single entry point for Next.js 16 work in app/. Load references/ on demand — do not paste reference bodies here.

Stack: Next.js 16.1.x · React 19 · Turbopack · App Router · port 3002.

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When to load what

Task	Load
New route, layout, RSC, Server Action, metadata	This skill + reference row below
proxy.ts, next.config.ts, v16 caching, Turbopack	references/ipix-16.md or nextjs-16
Supabase auth, cookies, callback, session	ipix-supabase → references/auth/nextjs.md
Core Web Vitals, bundle, image perf	vercel-react-best-practices
Client hooks / Suspense leaf	react-patterns

Do not load together on small tasks: this hub + vercel-react-best-practices — pick architecture OR perf as primary.

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iPix rules (non-negotiable)

• Never add middleware.ts — network gate is app/src/proxy.ts only (IPI2-127).
• getMastra() only inside route handlers — never at module top-level (CLAUDE.md).
• Data layer: Supabase SSR + Mastra + CopilotKit — not generic ORM examples in references.
• Validate: cd app && npm run lint && npm run typecheck && npm test (+ npm run build when routes/config change).
• error.tsx gap: most operator routes still lack error boundaries — add when touching async segments.

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Reference guide

Topic	File	Load when
Next.js 16 / iPix platform	ipix-16.md	proxy, config, caching, MCP debug
App Router	app-router.md	layouts, route groups, conventions
Server Components	server-components.md	RSC, streaming, client boundaries
Server Actions	server-actions.md	forms, mutations, revalidation
Data fetching	data-fetching.md	fetch, ISR, tags
Deployment	deployment.md	Vercel, env, production build

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MUST / MUST NOT

MUST

• App Router (app/) only — no Pages Router
• Server Components by default; 'use client' at leaf only
• Explicit fetch cache / next.revalidate — no implicit caching assumptions
• generateMetadata or static metadata for SEO
• next/image for content images

MUST NOT

• Add middleware.ts (use proxy.ts)
• Fetch secrets in Client Components
• Skip loading.tsx on new async list routes
• Deploy without cd app && npm run build green

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Workflow

1. Architecture — routes, layouts, RSC vs client split
2. Implement — page/layout + data layer (Supabase server client)
3. Platform check — ipix-16 if touching config/proxy/caching
4. Verify — lint · typecheck · test · build in app/

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Archived (do not load)

Was	Use instead
archive/nextjs-best-practices	This hub + vercel-react-best-practices for perf
archive/nextjs-supabase-auth	ipix-supabase → references/auth/nextjs.md
archive/nextjs-app-router-patterns	references/app-router.md

Upstream docs