Ever wanted to truly explore what it would be like to be a James Gosling, or a Bjarne Stroustrup, or Anders Hejlsberg? Want to see what it's really like, building a language from soup to nuts? This presentation will take you through that process exactly, from deciding whether your language will be compiled or interpreted, or static- or dynamically-typed, through defining a simple grammar, building the parser, constructing the AST, and generating code out the back end. We'll look at tools that can simplify this process, and discover that building a custom language for a particular task isn't quite as hard as it might seem at first. It's domain-specific languages, without the PhD.