Green Ticks, Wrong Numbers: Data Contracts and Data Quality

Deep End Era. Engineering with Sankalp · Oct 28, 2026 · 1h

At 7:40 on a Monday, a CFO sees revenue down eleven percent and asks one question: is this real? Every pipeline is green. Data platform engineer Tobiah Mensah-Lund and head of data Priyanka Halvorsen trace the drop to a new order status, partially fulfilled, that a revenue filter silently excluded. In episode one hundred and forty eight we learn why data bugs are silent, from the Mars Climate Orbiter's units to the 15,841 COVID cases lost to an XLS row limit; what schemas, Avro and schema registries can and cannot promise; how data contracts treat datasets as APIs; why dbt tests muted to…