Video and slides synchronized, mp3 and slide download available at URL http://bit.ly/1IEleaz. Dan North describes a model for thinking about the age of code and argues for replaceability as a first class concern. He also discovers that if one optimizes for both replaceability and consistency he can end up with something that looks a lot like microservices. Filmed at qconlondon.com. Dan North uses his deep technical and organisational knowledge to help CIOs, business and software teams to deliver quickly and successfully. He puts people first and finds simple, pragmatic solutions to business and technical problems, often using Lean and Agile techniques.