Worked on the folio-org/mod-circulation repository, focusing on backend development and permissions management using Java. Addressed a critical security issue by correcting the permissions update logic in the circulation module, specifically resolving the MODCAL-136 bug. The technical approach involved refining the authorization update flow to prevent permission-related errors and ensure proper enforcement of access controls. No new features were introduced during this period, as the primary goal was to stabilize security-critical operations. The work improved the reliability of access control mechanisms, reducing the risk of unauthorized access and enhancing the overall security posture of the module’s circulation operations.