Shaun Kaasten developed dashboard rendering performance instrumentation for the getsentry/sentry repository, focusing on improving observability and enabling data-driven optimization. He implemented detailed tracking of React re-render durations triggered by window resize events on both the individual dashboard view and the Manage Dashboards page. Using TypeScript and React, Shaun extended existing performance measurement patterns with performance.now() and scheduleMicroTask to quantify JavaScript render costs during layout recalculations. Metrics were tagged by page to support granular analysis and comparison. This work provided end-to-end visibility into rendering efficiency, supporting future optimization and capacity planning, and demonstrated a thoughtful approach to instrumentation architecture.