Three years building other people's websites. One five-line bug that survived eleven releases. And the week I finally became a real engineer
https://nexiobit.com/
I shipped 11 versions chasing one bug. It was 5 lines: a parser that read "15:30" but not "3:30 PM". Every real customer types "3:30 PM". My code never crashed. It lied gracefully. That's worse.
The interesting milestone isn't fixing one stubborn bug—it's recognizing that engineering maturity comes less from the number of projects you've shipped and more from how deeply you investigate the failures that survive them. I'd keep validating whether that shift changes how you build future systems, not just how you debug the current one.