Detached DOM elements are invisible memory leaks that accumulate as users navigate your app. This talk explores how to build a production monitoring system that detects and attributes these leaks without impacting performance. We'll examine the architecture and engineering tradeoffs involved in background memory monitoring, explore modern browser APIs for non-blocking work scheduling, and discuss practical patterns for collecting production data at scale. From detection strategies to advanced scheduling techniques, you'll see how to balance observability with user experience in real-world applications.