NestJS Microservices on AWS: A Production Guide

Why NestJS on AWS Lambda?

The combination of NestJS's modular architecture and AWS Lambda's serverless scaling is powerful — but there are pitfalls.

Cold Start Mitigation

The biggest challenge with Lambda is cold starts. Here are strategies that work in production:

1. **Provisioned Concurrency** for latency-sensitive endpoints
2. **Keep functions small** — split monolithic Lambdas into focused handlers
3. **Lazy loading** — don't import everything at module initialization

Event-Driven Architecture

@Controller()
export class OrdersController {
  @EventPattern('order.created')
  async handleOrderCreated(@Payload() data: OrderCreatedEvent) {
    await this.ordersService.processOrder(data);
  }
}

Observability

Use AWS CloudWatch structured logging with correlation IDs to trace requests across services.

Conclusion

NestJS on AWS is production-ready when you respect the constraints of serverless.