nodejs-backend

Structure a Node.js backend by separating core business logic, infrastructure, HTTP, and configuration layers. Use factory-function route composition and dependency injection to wire Kysely repositories into Express handlers, keeping business logic pure and isolating side effects.

The best way to validate configuration and requests in a Node.js API is using Zod schemas. This approach ensures validated configuration and request payloads, satisfying predictable behavior from development through production while preventing fragile data handling.

Implement transactional database operations with Kysely by applying repository patterns that execute atomic DB operations. This ensures reliable data integrity for common tasks such as user creation and fund transfers within your Express or Fastify services.

Yes, you can use dependency injection for routes and repositories in Fastify services. Factory-function route composition wires repositories into Fastify handlers, isolating side effects and separating core business logic from infrastructure layers for predictable behavior.

Handle domain errors globally in a Node.js web API by defining domain-specific error types and routing them through a global error handler. This ensures predictable behavior and keeps business logic pure by centralizing error management.

Use unit and integration testing strategies tailored for a layered Node.js backend architecture. Testing practices validate the separation of core business logic and infrastructure layers, ensuring reliable behavior from development through production.