Kaiqi Dong enhanced the apache/flink repository by enabling dynamic expression support for the to_timestamp_ltz function in PyFlink SQL queries. This work allowed expressions, rather than just literals, to be used as arguments, increasing flexibility in timestamp conversions. Kaiqi updated the expression generation logic in Python to accommodate dynamic inputs and implemented comprehensive tests to ensure regression safety. Leveraging skills in Data Engineering, PyFlink, and SQL, Kaiqi’s contribution addressed the requirements of FLINK-38319 and improved PyFlink’s usability. The depth of the work is reflected in the careful integration and validation of new functionality within the existing codebase and test suite.