Worked on the spring-projects/spring-authorization-server repository, delivering a backend feature that enhances client registration by including the client_secret_expires_at timestamp in the registration response. Leveraging Java, Spring Security, and OAuth2/OIDC protocols, the implementation ensures that the expiration date for client secrets is both returned and persisted, improving visibility into client lifecycle management. Comprehensive tests were added to verify the accuracy and persistence of the expiration timestamp across registration flows. This targeted enhancement supports better secret rotation and risk management, reflecting a focused approach to security-conscious backend development within the project’s established architecture and standards. No bug fixes were recorded.