Worked on the acidanthera/audk repository with a focus on firmware engineering and UEFI development, specifically targeting reliability and data integrity within the VarStore/UI subsystem. Addressed a critical bug in the MdeModulePkg/HiiDatabase by correcting the default value sizing for BIT VarStores, ensuring that defaults are consistently copied as UINT32 regardless of bit width. This fix prevented potential data corruption for CheckBox, OneOf, and Numeric data types referencing Bit EFI VarStores. The work, implemented in C, emphasized correctness, stability, and maintainability, enhancing the robustness of VarStore handling without introducing new user-facing features during the development period.