During December 2024, Zhihao Zhang enhanced the IBM/velox repository by developing a regression test to ensure that LocalPartition’s kGather operation preserves input order during serial execution. He designed a test harness in C++ that processes multiple input vectors and applies a window function to validate deterministic output, directly addressing regression #11726. Although no new production features were added, his work improved test coverage and reliability for serial execution semantics in the LocalPartition path. By focusing on data processing and rigorous testing, Zhihao’s contribution reduced the risk of order-related regressions and strengthened the overall correctness of the codebase.