Keep in mind the timings in the first blog are 4 years old and the second blog are 2 years old. Both Java and Clojure have made improvements and released new ve

Keep in mind the timings in the first blog are 4 years old and the second blog are 2 years old. Both Java and Clojure have made improvements and released new versions.A simple hello world uberjar with the default settings is about 0.775 s for me. Also, Clojure can be AOT compiled with direct-linking and elided metadata which alleviate some of the broader concerns (they're unlikely to affect a hello world type app though). See: http://clojure.org/reference/compilation http://clojure.org/reference/compilation Var class loading is still a concern, so there is of course still room for improvement. Experiments in this area are ongoing. Delayed var loading has the significant downside of making every var call thereafter slower (as the code needs a guard to check whether the class has been loaded or not). invokedynamic shows some promise is getting the best of both worlds there.