I have been using it for my (modestly sized) first serious public project (https://github.com/domovikapp/domovik-server/ https://github.com/domovikapp/domovik-s

I have been using it for my (modestly sized) first serious public project (https://github.com/domovikapp/domovik-server/ https://github.com/domovikapp/domovik-server/), and I have been quite satisfied with it. For the pluses: - the development experience is stellar (live code reload, REPL interacting directly with the running server, excellent debugger, dependencies management & build system are good and can be extended in the language itself); - the integrated documentation generator is of high quality; - the performances are satisfactory (you'll get more out of a $10/m VPS with Elixir/Phoenix than with RoR); - deployment is surprisingly easy with the releases system; - the language itself is quite pleasing; - the standard library is very well designed and architectured, and everything just fall in place together; - Ecto shows brilliantly how to combine high-level, ORM-like operations and low-level, close-to-the-SQL ones; - Phoenix itself is a very well though out framework. For the cons: - the ecosystem is still quite young and has some sharp edges and/or missing docs; - the OTP is magic for heavily parallel workloads, but it is also quite foreign and there will be some work to grasp its inner workings; - there are some quirks in the language coming from the Erlang runtime; - I would love to have a static type system, although I see how it would conflict with the tenets of the OTP. So all in all I might not recommend it for a very high stakes project; but otherwise, just go for it, it's great.