Jacobin[0] a JVM written in entirely in go. While we still have a way to go to get to feature parity for Java 21, we can sit back and watch the bytecode instructions fly by as they execute, which is something you can't do with the JDK due to the HotSpot JVM's architecture and the fact that it's written in both Java and C++.

We just crossed 5,000 commits. Also, we take testing very seriously: our test code base is presently 160% the size of our production code.

[0] jacobin.org