Node.js / NestJS

Node.js / NestJS

BACKEND

Backend development with Node.js runtime and NestJS TypeScript-first framework. Modular architecture with decorators, dependency injection and full TypeScript support for building highly maintainable REST APIs, GraphQL and enterprise-grade microservices.

What you'll learn

NestJS framework with modular architecture and decorators (@Controller, @Injectable)

Strict TypeScript with advanced types and automatic inference

Native Dependency Injection with IoC container and scopes

Controllers, Providers, Modules for clear code organization

Guards for authentication, Pipes for validation, Interceptors for transformation

TypeORM or Prisma for ORM with migrations and complex relationships

Integrated Passport.js for auth strategies (JWT, OAuth2, local)

GraphQL with code-first or schema-first approach

Microservices with transport layers (TCP, Redis, gRPC, MQTT)

Comprehensive testing (Jest, E2E, unit tests, mocking, coverage)

Key topics to master

The most important concepts to understand this technology and ace your interviews

1

Node.js: Event Loop, non-blocking I/O, async/await, streams, buffers

2

NestJS architecture: modules, controllers, providers, decorators

3

Dependency Injection: providers, scopes (DEFAULT, REQUEST, TRANSIENT), custom providers

4

Controllers and routing: @Get, @Post, @Param, @Body, @Query, route params

5

Providers and services: business logic, repository pattern, service layer

6

Middleware, Guards, Interceptors, Pipes, ExceptionFilters (request lifecycle)

7

Validation with class-validator and class-transformer (DTO validation)

8

TypeORM: entities, relations (@OneToMany, @ManyToOne), repositories, QueryBuilder

9

Prisma: schema, migrations, client, relations, transactions

10

Authentication: Passport.js, JWT strategy, guards, role-based access control

11

Configuration: ConfigModule, environment variables, validation

12

Exception handling: HttpException, custom exceptions, filters

13

Testing: unit tests with Jest, E2E tests, mocking, test doubles

14

GraphQL: resolvers, schemas, mutations, subscriptions, DataLoader

15

Microservices: patterns (request-response, event-based), transporters

16

Performance: caching (Redis), compression, rate limiting, profiling

17

Logging (Winston, Pino), monitoring, Docker, deployment