Briefly, the JVM starts very quickly.  Most of the time is spent loading the clojure.core namespace.  See <a href="http:&#x2F;&#x2F;blog.ndk.io&#x2F;jvm-slow-startup.html" rel="nofollow">http:&#x2F;&#x2F;blog.ndk.io&#x2F;jvm-slow-startup.html</a>