The tools and processes we use to transform our system's source code into an application that we can deploy or ship have always been important, but nowadays they can mean the difference between success and failure. The reasons are simple: larger code bodies; teams that are bigger, more fluid, and more widely distributed; richer interactions with other code; and sophisticated tool chains. All these mean that a slapdash software build process will be an endless drain on productivity and an embarrassing source of bugs, while a high-quality one will give us developers more time and traction to build better software.