Session abstract
What you’ll learn
Building APIs with Java and Spring Boot is relatively easy at the beginning, but many applications develop design and maintainability problems as they grow. Small mistakes in API structure, validation, exception handling, and application layering can eventually lead to difficult debugging, poor system reliability, and technical debt. In this session, we will explore five common mistakes developers make when building backend APIs and how to correct them using practical engineering approaches. Through examples using Java and Spring Boot, we will examine how these issues appear in real projects and how applying better design practices can improve reliability and maintainability. This talk focuses on practical techniques developers can apply immediately when building backend services. Topics covered include: • Designing consistent and predictable REST API endpoints • Implementing proper request validation using Spring Boot • Structuring exception handling for clear and reliable error responses • Separating responsibilities between controllers, services, and repositories • Using DTOs to prevent exposing internal database entities Attendees will leave with concrete patterns and practices that help build cleaner, more maintainable Java APIs.