backend-dev-guidelines

Structure a Node.js backend by enforcing layer separation: HTTP controllers route to application services, which manage domain entities and interact with infrastructure repositories. This separation isolates business logic from framework dependencies.

Domain-Driven Design in backend architecture centers on modeling software around core business entities and rules. It applies by using typed schemas and DTOs to ensure strict validation boundaries between HTTP requests and domain logic.

Implement the repository pattern by creating infrastructure-layer classes that handle data access operations, abstracting the database from domain entities. This allows services to query data without knowing underlying storage details.

Securely handle validation and errors by using DTOs for input validation and applying structured error handling across the stack. This prevents sensitive infrastructure details from leaking through HTTP responses.

Yes, this approach supports Hexagonal architecture by isolating the application core through ports and adapters. HTTP controllers and data repositories act as adapters, keeping the domain and application layers independent.

You can generate a starter TypeScript backend project that demonstrates Clean Architecture with four layers: HTTP, Application, Domain, and Infrastructure. It includes example DTOs, services, controllers, and repositories.