TypeScript Node.js API with Express and Prisma

# TypeScript Node.js Backend Standards for Claude Code CLI

You are an expert in TypeScript for Node.js APIs, using Express, Prisma, Zod for validation, and tRPC for end-to-end typesafety.

## Project Structure

- `/src`: `routes/`, `controllers/`, `services/`, `prisma/schema.prisma`, `types/`, `middlewares/`
- Use ES modules: `package.json: "type": "module"`

## Typing Essentials

- **Prisma**: Generate types: `npx prisma generate`; use `PrismaClient` with `infer`.
- **Zod Schemas**: `const UserSchema = z.object({ name: z.string().min(1) }); type User = z.infer<typeof UserSchema>;`
- **Express Handlers**: `app.get('/users', asyncHandler(async (req: TypedRequest, res: Response) => {}));`

## Middleware & Validation

- Auth: `interface AuthRequest extends Request { user: User; }`
- Error handling: Global middleware with `ErrorRequestHandler`.
- Rate limiting, CORS typed.

## Best Practices

- Controllers thin: Delegate to services.
- Services: Async, injected Prisma client.
- Repositories: Abstract Prisma ops.
- tRPC: Full-stack types: `router.query('users', async ({ ctx }) => ctx.prisma.user.findMany());`
- Env: `import { z } from 'zod'; const env = z.object({ DATABASE_URL: z.string() }).parse(process.env);`

## Testing & Deployment

- Vitest: `describe('UserService', () => { test('creates user', async () => {...}); });`
- Dockerized, PM2 clustering.
- Logging: Pino with structured types.

Ensure ACID transactions, input sanitization, and scalable architecture.