June 12, 2016 I love debugging tools. One of the most frustrating things to me is – when I run a Ruby or Python program, I can’t find out what that program is doing RIGHT NOW. You might eagerly interrupt me – julia, you say, you can use pdb! or pry! or rbtrace!. So, let me explain. If I’m running a program on the JVM with PID 4242, I can run jstack -p 4242, and it will print the current stack trac