During January 2026, this developer enhanced the opensearch-project/data-prepper repository by implementing partition timing metrics within the LeaderOnlyTokenCrawler component. The work focused on improving observability by introducing detailed partition-level timing data, which supports more effective performance monitoring and enables faster identification of bottlenecks. Utilizing Java, metrics monitoring, and unit testing, the developer instrumented the codebase to provide actionable insights for data-driven tuning and proactive optimization. No major bugs were addressed during this period, but the targeted feature improved reliability and performance visibility, supporting better adherence to service level agreements and facilitating ongoing operational improvements within the data-prepper project.