This is not exactly true. The JVM startup time is not what makes Clojure slow to load; it's the startup of Clojure itself. ~$ time clj test.clj Hello

This is not exactly true. The JVM startup time is not what makes Clojure slow to load; it's the startup of Clojure itself. ~$ time clj test.clj Hello world! real 0m1.337s user 0m1.309s sys 0m0.172s ~$ time java Test Hello world! real 0m0.142s user 0m0.116s sys 0m0.030s You may want to look at the -XX:+TieredCompilation -Xbootclasspath flags. They reduced the clojure startup significantly for me.