As our company developed through startup and scale up phases, our systems grew larger and more complex. Our usage increased dramatically and our requirements ballooned. In this session, we will look at how our software and architecture developed into a Conway’s law spider web of interdependent services. We will show how we used domain driven principles to give our systems structure and provide guidance to our developers. We will study the complexities of operating in the health care industry and analyse the strategies we used and the lessons learned as the company evolved and found product market fit.