Most marketing teams still struggle to connect the dots between fragmented datasets—campaign configs, attribution signals, incrementality tests, and spend logs. Uber tackles this by building a marketing semantic layer: a shared data foundation that stitches together marketing concepts, metrics, and identifiers across sources to create a single, queryable source of truth. Seojoon unpacks how they designed their semantic layer and its companion “context registry,” which captures the evolving business meaning behind metrics and entities. Learn how this system helps analysts, scientists, and marketers interpret performance shifts faster, automate root cause analysis, and reduce time spent reconciling inconsistent data definitions. Expect a grounded walkthrough—not theory—of the architecture, governance model, and cultural changes behind making marketing data truly interoperable.