Worked on the fmtlib/fmt repository to address a macro-related bug affecting formatting reliability in C codebases. Focused on improving macro robustness by wrapping macro arguments in parentheses, this change prevented mis-evaluation and stabilized macro behavior across diverse usage scenarios. The solution targeted edge-case failures, aligning with project goals for stability and maintainability while ensuring no performance regressions. Collaborated with external contributors through code review, reinforcing a thorough and careful development process. Utilized C programming and macro development expertise to deliver a targeted fix that improved code health and reliability for downstream users relying on consistent macro functionality in fmtlib/fmt.