Contributed to the yuwata/systemd repository by developing a fallback printf format parser to improve Musl compatibility. This work involved implementing a robust parse_printf_format() function in C, focusing on precise type handling and state management for various printf specifiers. The solution addressed the need for reliable formatted output on Musl-based systems, enhancing both portability and stability across different deployment environments. The approach demonstrated skills in C programming, library development, and system programming, with careful attention to maintainability and collaborative development practices. No major bugs were fixed during this period, as the primary focus was on feature enhancement and compatibility improvements.