During October 2025, Pavel Filippov focused on backend reliability for the folio-org/mod-dcb repository by addressing a bug in the Inventory Location API. He resolved an issue with the isShadow field’s JSON serialization in both LocationUnitClient and LocationsClient, which previously caused errors when fetching inventory location data. Pavel’s approach included implementing targeted unit tests to ensure correct serialization behavior and prevent future regressions. Working primarily with Java, API integration, and unit testing, he enhanced data integrity and API resilience in production. The work demonstrated careful attention to traceability and maintainability, with all changes clearly linked to the MODDCB-240 issue.