JVM startup time is slower than a lot of VMs, but it's not that slow. Write a hello world in Java and see how long it takes, I'd guess 100ms or so. Do the same in Clojure and you're looking at 3-4 seconds.
This is why I think ClojureScript/Node should become the "default" environment for writing Clojure. It would open up Clojure to a new class of apps that are currently not practical.
A hello world in java however has next to zero depedencies.
The jvm startup is notoriously slow keeping your jvm warm yields excellent results. Just try it please.
Things like nailgun exist for this exact reason.
I can't see them porting the cross compilation of clojurescript to node.
This is a good analysis of why Clojure startup is slow: http://nicholaskariniemi.github.io/2014/02/25/clojure-bootst...
This is why I think ClojureScript/Node should become the "default" environment for writing Clojure. It would open up Clojure to a new class of apps that are currently not practical.