During January 2025, Efron focused on backend development for the Difegue/LANraragi repository, addressing data accuracy and reliability in metadata operations. He resolved a bug in Redis item count retrieval by replacing the zcard command with zcount, ensuring precise differentiation between total and filtered counts for Tankoubon processing. Working in Perl, he improved the handling of undefined metadata fields to prevent downstream errors in user-facing features. Efron also enhanced the project’s testing framework by adding and updating assertions for the Tankoubon model, which strengthened regression protection and overall test coverage. His work demonstrated careful attention to data integrity and maintainability.