This is for an empty program. Serious Java programs (especially those that pull in a lot of libraries) can easily take >1s to start up. Running jruby on an empt

This is for an empty program. Serious Java programs (especially those that pull in a lot of libraries) can easily take >1s to start up. Running jruby on an empty file takes 1.4s wall clock time and nearly 4s of CPU time for me. Time to compile a hello-world program with Kotlin is 1.9s wall clock time and over 4s CPU time. It's worse with Scala. If I want to write code that (say) is run dozens of times during a large build process, that's not really acceptable. The JVM is a poor fit for the Unix model in particular, which tend to use lots of small processes with a single purpose that work together. Yes, there are workarounds (been there, done that), but the larger point is that the JVM and its ecosystem are primarily targeted at fairly heavy-weight and long-lived server processes that have obvious implementation biases along these lines. The slow startup time is just one symptom of these implementation biases, and the question is not whether you can work around these problems, but why you should bother in the first place if the JVM is a poor fit for your application domain.