Apollo Elon focused on enhancing the correctness and stability of Spark integration within the apache/paimon repository. During January 2026, Apollo addressed a critical bug by refining null handling in the EqualNullSafe predicate used by SparkV2FilterConverter, ensuring accurate query results when columns contain null values. This work involved updating related filtering logic and expanding unit tests to cover various null scenarios, thereby increasing test coverage and reducing the risk of regressions. Utilizing Scala, Spark, and unit testing, Apollo’s contributions improved data reliability for analytics workloads and provided clear commit traceability, reflecting a methodical approach to maintaining robust data processing systems.