Under JVM, Quasar can provide the same capability. And this is the Java code (using Quasar), translated from Go pretty much line by line. Quasar will use the exception or the annotation to determine when the JVM starts what to rewrite. So any code lacking these markings will per. That's easy too: a Quasar fiber is used exactly like a Java thread, and by that I mean it implements the thread API. Quasar abstracts both thread.