In December 2025, Mingjie Deng expanded the Spark SQL map function capacity within the facebookincubator/velox repository, increasing support from three to ten key-value pairs to enable more complex data mappings in Spark-based data transformation pipelines. Working primarily in C++ and leveraging Spark SQL, Mingjie designed, implemented, and tested the feature end-to-end, collaborating closely with reviewers to ensure maintainability and code quality. The work included thorough documentation and unit testing, reflecting disciplined engineering practices. By broadening the function’s capabilities, Mingjie reduced the need for workarounds in Spark workflows and enhanced Velox’s integration with Spark for diverse customer use cases.