Join Calculus is a little-known programming paradigm for purely functional concurrency. Join Calculus develops upon the Actor model to make concurrent programming less imperative, type-safe, deadlock-free, and even more intuitive. I give an introduction to Join Calculus and present examples such as the "dining philosophers" problem and a concurrent merge sort. I present a prototype implementation of Join Calculus as an embedded Scala DSL, based on previous work of Philipp Haller and Jiansen He.
