During December 2024, Brnsb developed cross-backend arg_min and arg_max APIs for Series and Expression in the narwhals-dev/narwhals repository. This work unified the retrieval of index positions for minimum and maximum values across Pandas, Polars, and PyArrow, streamlining analytics workflows and reducing code duplication. Brnsb focused on API design and library development in Python, ensuring consistent behavior and parity between Series and Expression interfaces. The implementation stabilized core analytics paths without introducing critical bugs, laying groundwork for future optimizations. Through careful testing and attention to backend compatibility, Brnsb delivered a robust feature that enhances cross-platform data analysis capabilities.