node-backend

Node.js Backend

Patterns and best practices for Node.js backend development with TypeScript.

Framework Selection

| Framework | Best For | Use When | |-----------|----------|----------| | Express | Simple APIs, flexibility | Quick setup, full control needed | | NestJS | Enterprise, structured | Large teams, Angular-like structure | | Fastify | Performance critical | High throughput, schema validation | | Hono | Edge, lightweight | Cloudflare Workers, minimal overhead |

Reference Files

| Topic | Load | Use When | |-------|------|----------| | Project structure | references/project-structure.md | Setting up new project or organizing code | | Express patterns | references/express-patterns.md | Building with Express | | NestJS patterns | references/nestjs-patterns.md | Building with NestJS | | Auth implementation | references/auth-patterns.md | Implementing authentication | | Error handling | references/error-handling.md | Setting up error handling | | Validation | references/validation.md | Input validation patterns |

Quick Start Patterns

Express Basic Setup

import express from 'express';
import cors from 'cors';
import helmet from 'helmet';
import { errorHandler } from './middleware/errorHandler';
import { routes } from './routes';

const app = express();

app.use(helmet());
app.use(cors());
app.use(express.json());

app.use('/api', routes);
app.use(errorHandler);

export { app };

NestJS Module Pattern

@Module({
  imports: [TypeOrmModule.forFeature([User])],
  controllers: [UsersController],
  providers: [UsersService],
  exports: [UsersService],
})
export class UsersModule {}

TypeScript Configuration

{
  "compilerOptions": {
    "target": "ES2022",
    "module": "NodeNext",
    "moduleResolution": "NodeNext",
    "strict": true,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "outDir": "./dist",
    "rootDir": "./src",
    "declaration": true
  }
}

Essential Packages

| Package | Purpose | |---------|---------| | typescript | Type safety | | zod | Runtime validation | | bcrypt | Password hashing | | jsonwebtoken | JWT handling | | helmet | Security headers | | cors | CORS handling | | winston / pino | Logging | | prisma / drizzle | Database ORM |

Code Quality Rules

1. Always use TypeScript - strict mode enabled
2. Validate all inputs - use Zod or class-validator
3. Handle all errors - never swallow exceptions
4. Use async/await - no callback hell
5. Environment variables - use dotenv, never hardcode secrets
6. Logging - structured logs with correlation IDs