During February 2025, contributed to the spring-security repository by implementing a configurable JWK Key Selection Strategy for the NimbusJwtEncoder component. This feature introduced a converter-based strategy pattern, allowing users to define custom logic for selecting signing keys from a list of JWKs, thereby supporting more flexible and policy-driven key management. The work focused on enhancing JWT signing flexibility and preparing the system for robust key rotation and multi-key management scenarios. Leveraging Java, Spring Security architecture, and the Nimbus JOSE + JWT library, the contribution improved secure key management practices while maintaining a minimal API surface and clear integration with existing backend workflows.