backend-api-patterns

To separate data access from business logic in a backend API, apply the repository pattern. This approach isolates data operations, improving testability and flexibility while maintaining clear boundaries between service layers and data access components.

The best way to handle transactions across multiple repositories is the unit of work pattern. It coordinates consistent commits and rollbacks, ensuring data integrity across service layers when building scalable backend APIs.

Implement consistent error handling and logging in scalable APIs by using standardized error classes alongside a global handler. This mechanism provides meaningful, uniform responses and observability across all backend service endpoints.

For backend API security and performance, use patterns covering input validation, authorization, caching, and rate limiting. These architectural patterns ensure robust, scalable APIs by preventing unauthorized access and managing traffic loads efficiently.

You do not need to design a new microservice architecture from scratch to use these API patterns. They can be applied to new endpoints and service layers within existing projects to ensure maintainable code and predictable behavior.

Inconsistent backend architecture leads to brittle services because it lacks clear boundaries between data access, business logic, and API layers. This coupling creates maintenance headaches and unpredictable behavior when updating endpoints or scaling systems.