Worked on the fmtlib/fmt repository to address a critical build stability issue affecting users of modern Clang toolchains. Focused on C++ development and build system management, the work involved fixing the F-string constructor initialization with 'sv', which previously caused build failures on Tip-of-Tree clang. The solution was implemented and validated through a targeted code change, ensuring that continuous integration pipelines run reliably and reducing flakiness for downstream users. By resolving this bug, the developer contributed to more robust and predictable builds, leveraging expertise in C++ and build systems to maintain compatibility with evolving compiler environments and toolchains.