STM, REPL, and data driven nature of Clojure. I know most people don't use STM in Clojure, but I find it to be a killer feature for some projects. Combined wi

STM, REPL, and data driven nature of Clojure. I know most people don't use STM in Clojure, but I find it to be a killer feature for some projects. Combined with pervasive immutability and it enables concurrent designs that are very difficult to pull off in other languages. For Elixir, the concurrency model and supervisor trees. It's a perfect fit for some problems, and in general as a small company, the projects we use Elixir on greatly simplifies our production environment which is always a win. Most of my focus when designing a project is to enable people with less experience than me to contribute in a bug-free fashion in the face of concurrency and parallelism. Sometimes that involves picking a funny language, sometimes it doesn't.