Worked on the VirtoCommerce/vc-module-x-cart repository to deliver an extensible Cart Shipment Handling feature focused on enabling merchant-specific customization and scalable shipment workflows. Applied backend development and object-oriented programming skills in C# to refactor the AddOrUpdateCartShipmentCommandHandler, converting private methods to protected virtual for safer extension and clearer separation of concerns. Introduced cancellation tokens to asynchronous shipment-handling methods, improving resource management and responsiveness during long-running operations. The approach emphasized maintainability and future-proofing, allowing for easier customization without altering core logic. The work demonstrated a strong grasp of refactoring principles and design for extensibility within a .NET environment.