I experienced this same moment when I was ~24 years old and digging through a codebase I'd written a few years prior after returning to a former employer. Once

I experienced this same moment when I was ~24 years old and digging through a codebase I'd written a few years prior after returning to a former employer. Once you've hit rock-bottom there's no place to go but up :P. I've subsequently noticed that those who are quickest to talk trash about nuanced engineering decisions and minor bugs are often the ones with the most fundamentally-indefensible coding practices (5000-line source files that throw innumerable compiler warnings, using deprecated frameworks, explicit silent failure modes, etc). Latent insecurity is a very real phenomenon.