But in order to do that, it does some interesting things under the hood, and it doesn't play nicely with reflection by default (amongst other things). For some non-Java JVM languages that's a major problem since their compiler produces JVM byte code that relies heavily on reflection (Groovy is/was a great example of this). I'm unsure how much, if any, reflection Clojure relies on but that would be the most likely reason for it to struggle with GraalVM compatibility.