I got a VIC-20 when I was about 12? Jim Butterfield loomed impossibly large over all things Commodore at that time. One of the first things I typed in on it was his TINYMON, a <1kbyte “monitor” (for some reason resident debuggers were frequently called monitors in early microcomputing) before I had any idea what it was.
[0] https://archive.org/details/Machine_Language_for_the_Commodo...