We tackle unique business challenges but are solving similar problems, and all too rarely will we talk through our designs and mistakes. Integrations, external APIs, data-stores - these might not be pure code but we can learn a lot from good object design when scaling our systems. In this talk we’ll discuss how parts of a distributed systems rely on each other, how data flow can couple and propagate failure, and how common emergent patterns can encapsulate services to be resilient. This is a journey of close calls, errors, and design smells researched into how a service gets simplified.