Becoming a professional programmer in the days of Test Driven Development, many are led to believe that there is only one approach to software design and that everyone else is wrong. But what if you’re also a Type fanatic who prefers the safety of compile time error messages? Can these two methods live in harmony? Should they? In this talk we’ll take a rational look across the spectrum of Test and Type driven design, examining the benefits and limitations of these approaches, as well as the language and framework features that best serve these differing needs.