Tianyi Hao focused on improving the reliability of graph operations in the tqec/tqec repository by addressing a critical bug in the BlockGraph relabeling workflow. Using Python and core software development skills, Tianyi fixed an issue where the _ports dictionary was not correctly updated when port labels changed in BlockGraph.relabel_cubes. This technical solution ensured that mappings from port labels to their corresponding cube objects remained accurate after relabeling, thereby maintaining graph integrity and reducing the risk of downstream errors. The work demonstrated careful attention to data consistency and contributed to a more stable foundation for future graph-based features.