During January 2025, Sam Johnson focused on enhancing the matrix-free pathways in the dealii/dealii repository, addressing a critical bug in 1D face setup and periodic neighbor handling. He improved ownership semantics when neighbors lacked children and refined subface index handling for periodic neighbors across both 1D and higher-dimensional cases. Working primarily in C++ and leveraging expertise in finite element methods and mesh handling, Sam delivered a targeted fix that increased solver robustness and reliability. His work laid the foundation for future scalability by ensuring correctness in complex mesh scenarios, demonstrating depth in both technical understanding and codebase integration.