∃xistential Type is a blog for people who like type and types. That is "type" in the sense of typefaces and typography, and "types" as in programming languages, and logic and type theory. It is written by Geoff Washburn, who works at LogicBlox on an industrial-strength version of the Datalog language. In the past, Geoff has worked on coinductive proof assistants, a formal foundation for the Scala language, reflection, and information-flow security.