NestJS Tutorial

Learn what NestJS is, what problems it solves, and how it helps you build organized Node.js backends.

Compare NestJS and Express so you can choose the right tool for small scripts, APIs, teams, and long-term apps.

See how this tutorial teaches TypeScript exactly when NestJS needs it, using realistic backend examples.

Install the Nest CLI, create your first project, run it locally, and understand the starter commands.

Understand the important files and folders in a new NestJS project before you start editing.

Learn the TypeScript essentials you will use constantly in NestJS: types, arrays, classes, constructors, and decorators.

Learn how NestJS modules organize controllers, providers, imports, and exports.

Learn how controllers define HTTP routes and call services to produce responses.

Understand providers, services, @Injectable, and where application logic belongs.

Learn how NestJS gives classes the dependencies they need and why that makes code easier to test and maintain.

Build routes with @Get, @Post, @Patch, @Delete, path prefixes, and REST-style naming.

Read route parameters, query strings, and request headers in NestJS controllers.

Use @Body and DTO classes to describe request data for create and update routes.

Validate DTOs with class-validator decorators and NestJS ValidationPipe.

Learn how pipes transform and validate incoming request values in NestJS.

Return useful HTTP status codes, response bodies, and headers in beginner-friendly NestJS controllers.

Use built-in HTTP exceptions and understand how exception filters shape error responses.

Load environment variables with @nestjs/config and use ConfigService safely in your app.

Understand shared modules, global modules, exports, and when to make utilities available across a NestJS app.

Learn the basic NestJS lifecycle hooks used during startup, shutdown, and module initialization.

Use watch mode, logs, curl, debugger habits, and common troubleshooting steps while building NestJS apps.

Learn the common create, read, update, delete pattern used by many NestJS REST APIs.

Organize a real feature folder with module, controller, service, DTOs, and clean imports.

Handle common beginner API error cases with clear exceptions, validation, and consistent service logic.

Put beginner NestJS concepts together by building a small validated Tasks API.

Use NestJS guards to decide whether a request can reach a route handler, with authentication and authorization examples.

Wrap request handling with interceptors for response mapping, timing, caching hooks, and cross-cutting behavior.

Use Nest middleware for request preprocessing, request IDs, raw logging, and compatibility with Express-style middleware.

Create custom parameter and metadata decorators to make controllers expressive without hiding business logic.

Understand authentication and authorization choices in NestJS before implementing JWT, sessions, Passport, and role checks.

Implement environment-configured JWT authentication in NestJS with login, token signing, and a route guard.

Integrate Passport strategies with NestJS for reusable local, JWT, and OAuth authentication flows.

Build role and permission authorization in NestJS with metadata decorators, Reflector, and guards.

Connect NestJS to relational databases with TypeORM entities, repositories, configuration, and service patterns.

Use Prisma as a type-safe database client in NestJS with a PrismaService, schema models, and clean service methods.

Connect NestJS to MongoDB with Mongoose schemas, models, DTOs, and service methods.

Treat database schema changes as versioned, reviewed, reversible operations instead of one-off edits.

Model relational data and nested API routes in NestJS without mixing routing concerns into persistence code.

Handle file uploads in NestJS with Multer interceptors, validation, storage decisions, and safe response design.

Use caching in NestJS to reduce repeated work while keeping correctness, invalidation, and TTLs in mind.

Move slow or retryable work out of request handlers with Bull queues, processors, and background jobs.

Run recurring or delayed application tasks with Nest schedule decorators and safe operational patterns.

Test Nest services, guards, and controllers in isolation with TestingModule, mocks, and focused assertions.

Test complete Nest HTTP flows with a real application instance, Supertest, validation, guards, and database setup.

Generate useful OpenAPI documentation for NestJS APIs with SwaggerModule, DTO decorators, tags, and auth metadata.

Add useful NestJS logs with Logger, request context, error details, and production-friendly practices.

Version NestJS APIs with URI, header, or media-type strategies while keeping compatibility promises clear.

Prepare NestJS applications for production with builds, environment variables, health checks, migrations, and process management.

Learn how to organize a NestJS codebase so features, modules, providers, and shared utilities stay understandable as the app grows.

Apply clean architecture ideas in NestJS with use cases, ports, adapters, and dependency injection tokens.

Understand commands, queries, handlers, events, and when the NestJS CQRS module is worth using.

Use events inside NestJS apps and understand the difference between local events, domain events, integration events, and reliable delivery.

Learn the NestJS microservices model, transports, message patterns, clients, contracts, and deployment tradeoffs.

Run HTTP routes and microservice listeners in one NestJS process while keeping lifecycle, health, and boundaries clear.

Build realtime features with NestJS gateways, Socket.IO events, rooms, authentication, and scaling considerations.

Learn the NestJS GraphQL basics: code-first schemas, resolvers, object types, inputs, auth, and avoiding N+1 queries.

Build a practical performance mindset for NestJS apps: measure first, optimize bottlenecks, and scale safely.

Harden a NestJS app with validation, authentication, authorization, secure headers, rate limits, password handling, and secret management.

Package a NestJS application for production with a multi-stage Dockerfile, .dockerignore, environment variables, and Docker Compose.

Understand production observability for NestJS: health checks, structured logs, metrics, traces, dashboards, and alerts.

Build a small but production-minded Tasks REST API with modules, DTOs, validation, service boundaries, and a clear folder structure.

Build a focused NestJS auth module with password hashing, JWT login, current user decorators, and role-based guards.

Build a realtime notifications foundation with an HTTP endpoint, a service, a WebSocket gateway, rooms, and a simple browser client.

Review common mistakes in advanced NestJS applications and learn practical fixes that improve maintainability and production safety.

Plan your next learning path after advanced NestJS: databases, testing, queues, GraphQL, DevOps, observability, and system design.