Worked on optimizing OneDrive On-Demand file scanning within the sandboxie-plus/Sandboxie repository, focusing on improving directory scan performance for hybrid cloud-aware file systems. Developed a targeted filtering mechanism in C++ that identifies and processes On-Demand files while avoiding the recall of cloud-backed offline files, thereby reducing unnecessary I/O operations. Leveraged system programming and file system operations expertise to implement precise checks using FILE_ATTRIBUTE_RECALL_ON_DATA_ACCESS and added detailed code comments to enhance maintainability. This feature laid the groundwork for future performance improvements and increased scanning accuracy, addressing the specific needs of environments where local and cloud storage coexist seamlessly.