main.ts

import { NestFactory } from '@nestjs/core';
import { Transport } from '@nestjs/microservices';
import { ApplicationModule } from './app.module';

async function bootstrap() {
  /**
   * Hybrid application (HTTP + TCP)
   * Switch to basic microservice with NestFactory.createMicroservice():
   *
   * const app = await NestFactory.createMicroservice(ApplicationModule, {
   *  transport: Transport.TCP,
   *  options: { retryAttempts: 5, retryDelay: 3000 },
   * });
   * await app.listenAsync();
   *
   */
  const app = await NestFactory.create(ApplicationModule);
  app.connectMicroservice({
    transport: Transport.TCP,
    options: { retryAttempts: 5, retryDelay: 3000 },
  });

  await app.startAllMicroservicesAsync();
  await app.listen(3001);
}
bootstrap();