entropic debugging - noun phrase - The phenomenon in which one can spend weeks on end debugging something using a multitude of techniques, give up in frustration and/or disgust for a couple of days, come back to the project and discover that somehow the bugs have magickally fixed themselves (as verified by diffs and file hashes if one cares to check). The phenomenon is so named due to the second law of thermodynamics, which states that entropy can never decrease, only increase in an isolated system. In other words, as entropy increases overall in the universe it somehow wiped out the bugs in question. See also kinetic pattern baldness.
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Time was, back in the days of the home 8-bit computers, we were very limited in what we could do in more than one way. Without even a proper reset button or development tools other than the built-in BASIC interpreter if something went wrong there was really no way that you could debug it. If you happened to be hacking code in any serious way on the Commodore chances are you'd shelled out good money for a debugger or disassembler and had at least a couple of reference books nearby. If you were doing everything in BASIC then either you were growing your program a few lines at a time or using some code you got out of a magazine to do low level programming from inside of BASIC (an exercise fraught with frustration, let me tell you). Even then, if something went sideways it was difficult to figure out where you went wrong and fix it. The tools just weren't common at the time. All you could really do was turn off the machine, wait a few seconds, turn it back on, and give it another shot in the hope that the machine wouldn't lock up on you again.
debuggery - noun - The unshakable feeling that your code is completely fucked when you spend multiple all nighters in a row tracking down a single annoying bug that winds up not being in your core code, nor any modules you've written, nor any of the libraries you're using, but in a different part of the system entirely. In other words, your code is so poorly architected that you can't tell when problems aren't actually in your code.