NestJS Mastery: Build, Secure and Test Production APIs with TypeScript and AI

This NestJS course takes you from a first module to a secured, tested backend API. The lessons build one learning-platform API feature by feature, so each concept lands on code you can run. You will learn to structure a NestJS application with modules, controllers and providers, and to inject dependencies cleanly. You will validate request bodies with DTOs, class-validator and a global ValidationPipe, then store data in PostgreSQL through TypeORM entities and repositories. Security is covered in depth: bcrypt password hashing, Passport JWT authentication, a JWT guard that loads the current user, role-based access with a roles guard, and rate limiting with the throttler. You will document endpoints with Swagger, write end-to-end tests against a separate test database, upload files to Cloudinary, cache paginated lists, and move slow work into BullMQ jobs. The course also covers WebSocket gateways, a RabbitMQ producer and consumer, Docker images pushed to a container registry, and an AI coding-agent workflow for building and reviewing NestJS code.