I spent almost four days trying to fix a bug that wasn’t actually in the code I was looking at.
I was about eight months into my first real developer job when a feature that worked perfectly on my machine started failing randomly in staging. It would work three times and then break on the fourth.
So I did what I thought I was supposed to do: rewrote functions, added console.log everywhere, restarted the server, and tried one fix after another.
Nothing worked.
Eventually, I stopped trying to fix it and started trying to understand the whole system. I mapped out the request flow and found a caching layer I didn’t even know existed.
The problem was a configuration value: 3000 had been entered instead of 300. What looked like a random bug was actually a timing issue.
That experience changed how I debug.
I used to immediately ask, “What did I write wrong?” Now I ask, “What am I assuming about this system that might not be true?”
Sometimes the problem isn’t in the function you’re staring at. It’s in the configuration, database, API, environment, or some old system nobody thought to document.
Real software is messy. It has history, old decisions, temporary fixes, and things you have to figure out as you go.
The biggest lesson wasn’t finding the bug.
It was learning that when something doesn’t make sense, slowing down and understanding the system is often faster than guessing.