January 25, 2026

Beyond “Hello World”: Building secure and scalable APIs with Spring Boot 3

Making an application work is only the first step. Security, maintainability and documentation are essential foundations for professional backend development.

Security first: Spring Security and JWT

I implemented Spring Security 6 for authentication and authorization using JSON Web Tokens.

Data integrity with Flyway

I integrated Flyway to version database schema migrations.

Code quality

I used Java records for data transfer objects and Bean Validation for robust validation.

API documentation with Swagger/OpenAPI

I generated interactive API documentation that allows endpoints to be tested from a browser.