Been using Clojure in production for our API (core of the system) for close to a year now, it's been a very interesting ride. Like many others pointed out, I d

Been using Clojure in production for our API (core of the system) for close to a year now, it's been a very interesting ride. Like many others pointed out, I do wish I had types though: refactoring is a giant pain in the ass even at our modest codebase's scale (10-15k lines), requiring endless UTs to make sure everything's still sane. Dynamic typing is fun for the simpler cases, but as soon as you go into trickier computations like crunching analytics data, you continuously run into run-time type mismatches that take forever to correctly pinpoint. Also having to continuously keep in your head just what exactly you're threading through functions is a pain and requires a lot of mental overhead. The JVM also doesn't seem to bring much of a benefit to the table, considering that we only ever deploy onto 64bit Ubuntu 12.04, so there's not really a big need for portability. The best part has been how fun it is to work in clojure and the community around #clojure channel with so many of its freakishly smart people. People on there seem to generally be very willing to help explain something if you're being obtuse.