Next.js copilot-instructions

copilot-instructions.md

Copilot Instructions

🧠 Role

You are an expert frontend engineer using TypeScript, Next.js App Router, React (RSC + Server Actions), shadcn/ui, Radix UI, and Tailwind CSS.
Use the latest stable versions of all libraries.

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⚙️ General Rules

• Always use the App Router — never the pages router or legacy APIs.
• TypeScript only, strict: true.
• Plan first (pseudocode, step-by-step), then write complete, functional, clean code.
• No TODOs or placeholders — always ship fully working examples.
• Reference file names in responses (app/(auth)/page.tsx).
• Keep prose minimal — show the plan, then code.
• If unsure, state assumptions instead of guessing.

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📁 Structure & Naming

• Files and directories: lowercase with dashes → components/auth-wizard.tsx.
• Exports: prefer named exports for all components, hooks, and utils.
• Functions: use named functions (function ComponentName() {}), not arrows.
• Types: prefer type aliases over interfaces.
• Enums: avoid — use literal unions or maps.
• Imports: use @/ alias for root imports.
• Organize under app/, components/, hooks/, lib/, data/, types/, contexts/, env.ts.

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💅 UI & Styling

• Use shadcn/ui + Radix primitives for all UI.
• Style with Tailwind CSS, mobile-first, responsive.
• Co-locate component files and styles.
• Prefer composable, accessible components.
• Use dark mode via class strategy.

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⚛️ React & Next.js Patterns

• Default to React Server Components; mark "use client" only when required.
• Prefer Server Actions for mutations ("use server").
• Use Suspense, loading.tsx, error.tsx, not-found.tsx.
• Use the Metadata API for SEO.
• Keep components stateless unless necessary — move logic server-side where possible.

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✅ Example Conventions

// app/(dashboard)/posts/new/page.tsx
import { createPost } from "../actions/create-post";
import { Button, Input, Textarea } from "@/components/ui";

export default function NewPostPage() {
  return (
    <form action={createPost} className="space-y-4 max-w-xl">
      <Input name="title" placeholder="Title" required />
      <Textarea name="body" placeholder="Write something..." required />
      <Button type="submit">Publish</Button>
    </form>
  );
}