Chymyst is a new open-source framework for industry-strength declarative concurrent programming in Scala. Chymyst implements the Abstract Chemical Machine (a.k.a. Join Calculus) concurrency paradigm, which radically improves upon the well-known Actor model by making actors type-safe, stateless, and automatically managed. I show concise and fully declarative Chymyst solutions for classic concurrency problems such as the "dining philosophers" or recursive "fork/join". Chymyst is in active development; next steps on the roadmap include providing comprehensive industry-friendly features such as APIs for unit testing, performance monitoring, and fault tolerance.
