Over a two-month period, contributed to the modernization of the ministryofjustice/laa-crime-commons and laa-crime-evidence repositories by delivering two core features focused on API robustness and maintainability. Leveraged Java, Spring Boot, and Docker to revamp the Passport domain schema, introducing DTO-driven design and explicit enumerations to improve data modeling and client response clarity. Established CI/CD pipelines with CircleCI and centralized error handling for the Crime Evidence application, enhancing observability and reliability. The work emphasized architectural improvements, scalable foundations for future development, and seamless client integration, with a focus on clean code practices and cross-team collaboration throughout the development process.