With functional programming gaining in popularity it's no surprise that purely functional languages would find their way to the browser. Elm is one such language. First released in 2012, Elm gives us immutability, algebraic data types, type safety, expressiveness, and the increased predictability of functional programming. In this session we'll construct a simple game in Elm. Along the way we'll explore many of Elm's features and discuss the benefits that purely functional programming brings to our Web applications.