March 2026 (2026-03) monthly summary for the apache/flink project. Focused on improving time semantics in the table planner to enhance accuracy of windowed operations and support BinaryRowData's non-compact timestamp format. Delivered a targeted feature to pass timestamp precision to window operators, addressing FLINK-38866. No major bugs fixed within the provided scope this month. The work improves correctness and reliability of streaming and batch windowed analytics, delivering clear business value for time-based processing pipelines. Technologies demonstrated include Java/Scala, Flink table planner internals, and BinaryRowData timestamp handling. Commit traceability: 4e088dec0f24e845809606ddacc2391dadfe6c73.

December 2025: Focused on API robustness for recovery paths in Apache Flink's HybridSource. Implemented a recovery-specific annotation by marking SourceSwitchContext#getPreviousEnumerator as nullable to reflect that it may return null during recovery (e.g., job restarts or checkpoint recovery). This clarifies the API contract, reduces potential misuse, and strengthens the stability of recovery flows for stateful jobs. Overall, the change improves reliability for recovery scenarios and enhances developer experience when working with recovery-related code.