Worked on the airbnb/chronon repository to enhance backfill reliability and user guidance by implementing a Backfill Skip Warning and Documentation Enhancement. Developed a mechanism in Scala to alert users when partitions are silently skipped due to the skipFirstHole setting, logging these events for improved observability during data processing. Updated documentation to clarify the behavior of the --run-first-hole flag, ensuring users understand default behaviors and recommended usage. Applied scalafmt formatting to maintain code clarity and maintainability, and contributed a bugfix addressing silent partition skipping. The work demonstrated a focus on backend development, robust logging, and clear communication through technical documentation.