For the server side, Clojure, by most metrics, would beat node.js by virtue of running on the JVM and its stellar concurrency capabilities. This includes ecosys

For the server side, Clojure, by most metrics, would beat node.js by virtue of running on the JVM and its stellar concurrency capabilities. This includes ecosystem, performance and scalability. Using ClojureScript in the browser gives you a language to use that's consistent with what you're using on the server, and easy interop (you can just send data back and forth directly, without having to do any extra serialization). It's also (in my opinion) a much better language than JavaScript. Learning curve is the one likely stickler - depends how inclined you are to learn a Lisp. Personally, I love it.