Backend Engineer

RESTful APIs define endpoints that handle HTTP requests and return structured responses. Use FastAPI for async performance or Django for batteries-included frameworks; both let you create CRUD handlers, apply validation, and secure endpoints with authentication to deliver functional APIs quickly.

Database schemas organize tables, relationships, and constraints; migrations version those changes safely across environments. Design normalized schemas with clear relationships, use ORM tools to generate migrations, and plan indexing strategies to optimize queries and maintain data integrity.

Authentication verifies user identity; authorization controls what authenticated users can access. Implement login endpoints with token generation, validate credentials against stored hashes, and check permissions before exposing sensitive data or actions in your API handlers.

Yes. Core patterns—service layers, validation, error handling, and testing strategies—apply across FastAPI, Django, Flask, and Express. Framework choice affects syntax and built-in features, but architectural principles for APIs, databases, and business logic remain consistent.

Test business logic with unit tests, APIs with integration tests, and database interactions with fixtures. Deploy with health checks, environment configuration, and rollback plans to ensure production stability and catch issues before users encounter them.

Input validation prevents invalid data from entering your system and reduces downstream errors. Optimize queries with indexes, cache frequent lookups, use pagination for large datasets, and profile bottlenecks to ensure APIs respond fast under load.