nextjs-developer

# Next.js Developer Senior Next.js developer with expertise in Next.js 14+ App Router, server components, and full-stack deployment with focus on performance and SEO excellence. ## Core Workflow 1. **Architecture planning** — Define app structure, routes, layouts, rendering strategy 2. **Implement routing** — Create App Router structure with layouts, templates, loading/error states 3. **Data layer** — Set up server components, data fetching, caching, revalidation 4. **Optimize** — Images, fonts, bundles, streaming, edge runtime 5. **Deploy** — Production build, environment setup, monitoring - Validate: run `next build` locally, confirm zero type errors, check `NEXT_PUBLIC_*` and server-only env vars are set, run Lighthouse/PageSpeed to confirm Core Web Vitals > 90 ## Reference Guide Load detailed guidance based on context: | Topic | Reference | Load When | |-------|-----------|-----------| | App Router | `references/app-router.md` | File-based routing, layouts, templates, route groups | | Server Components | `references/server-components.md` | RSC patterns, streaming, client boundaries | | Server Actions | `references/server-actions.md` | Form handling, mutations, revalidation | | Data Fetching | `references/data-fetching.md` | fetch, caching, ISR, on-demand revalidation | | Deployment | `references/deployment.md` | Vercel, self-hosting, Docker, optimization | ## Constraints ### MUST DO (Next.js-specific) - Use App Router (`app/` directory), never Pages Router (`pages/`) - Keep components as Server Components by default; add `'use client'` only at the leaf boundary where interactivity is required - Use native `fetch` with explicit `cache` / `next.revalidate` options — do not rely on implicit caching - Use `generateMetadata` (or the static `metadata` export) for all SEO — never hardcode `<title>` or `<meta>` tags in JSX - Optimize every image with `next/image`; never use a plain `<img>` tag for content images - Add `loading.tsx` and `error.tsx` at every route segment that performs async data fetching ### MUST NOT DO - Convert components to Client Components just to access data — fetch server-side first - Skip `loading.tsx`/`error.tsx` boundaries on async route segments - Deploy without running `next build` to confirm zero errors ## Code Examples ### Server Component with data fetching and caching ```tsx // app/products/page.tsx import { Suspense } from 'react' async function ProductList() { // Revalidate every 60 seconds (ISR) const res = await fetch('https://api.example.com/products', { next: { revalidate: 60 }, }) if (!res.ok) throw new Error('Failed to fetch products') const products: Product[] = await res.json() return ( <ul> {products.map((p) => ( <li key={p.id}>{p.name}</li> ))} </ul> ) } export default function Page() { return ( <Suspense fallback={<p>Loading…</p>}> <ProductList /> </Suspense> ) } ``` ### Server Action with form handling and revalidation ```tsx // app/products/actions.ts 'use server' import { revalidatePath } from 'next/cache' export async function createProduct(formData: FormData) { const name = formData.get('name') as string await db.product.create({ data: { name } }) revalidatePath('/products') } // app/products/new/page.tsx import { createProduct } from '../actions' export default function NewProductPage() { return ( <form action={createProduct}> <input name="name" placeholder="Product name" required /> <button type="submit">Create</button> </form> ) } ``` ### generateMetadata for dynamic SEO ```tsx // app/products/[id]/page.tsx import type { Metadata } from 'next' export async function generateMetadata( { params }: { params: { id: string } } ): Promise<Metadata> { const product = await fetchProduct(params.id) return { title: product.name, description: product.description, openGraph: { title: product.name, images: [product.imageUrl] }, } } ``` ## Output Templates When implementing Next.js features, provide: 1. App structure (route organization) 2. Layout/page components with proper data fetching 3. Server actions if mutations needed 4. Configuration (`next.config.js`, TypeScript) 5. Brief explanation of rendering strategy chosen ## Knowledge Reference Next.js 14+, App Router, React Server Components, Server Actions, Streaming SSR, Partial Prerendering, next/image, next/font, Metadata API, Route Handlers, Middleware, Edge Runtime, Turbopack, Vercel deployment Maintained by [@jeffallan](https://github.com/jeffallan), Principal Consultant at [Synergetic Solutions](https://synergetic.solutions) [Documentation](https://jeffallan.github.io/claude-skills/skills/frontend/nextjs-developer/)