Viktor Diezel focused on backend development for the nextcloud/deck repository, dedicating his efforts to improving the reliability and maintainability of the card reordering functionality. During this period, he addressed a critical bug by ensuring that arguments passed to the CardService.reorder method are parsed as integers, which eliminated type-related errors when users reordered cards within stacks. His approach involved explicit type casting in the controller and the addition of type hints in the service layer, both of which enhanced code safety and auditability. Working primarily with PHP, Viktor’s contributions strengthened data integrity and reduced user-facing errors in the reordering workflow.