Chase bugs like a pro: Save yourself from frustration

When I first started tackling algorithm and implementation challenges on HackerRank, I often found myself stuck on a bug for hours, staring at the screen and not knowing how to proceed.

I was a bit overconfident in my coding abilities. I thought I could just dive in, spot the error, and fix it on the fly without a structured approach. I quickly realized that this “cowboy coding” method was inefficient, frustrating, and honestly, unprofessional.

Over time, I developed a simple debugging checklist that helped me systematically identify and resolve issues. It eventually became our team’s standard operating procedure—when a bug had us stumped, we’d stop guessing and go through the list together.

Debugging can be daunting, especially in complex codebases. But having a structured approach turns panic into a process. Here is the checklist that changed my workflow.

1. Spot the Mismatch

What to do: Clearly state what you expected vs. what actually happened. Why it matters: If you can’t articulate the problem, you don’t understand it yet.

Are you expecting a user to stay logged in, but they are being redirected? Is a calculation off by one? I used to frequently find that my co-workers and I thought something was a bug, only to have a third party point out that it was actually a feature working exactly as intended. Defining the “mismatch” forces you to check the requirements first.

“I expect the user session to persist after refresh, but instead, the user is logged out.”

2. Reproduce Reliably

What to do: Find the exact steps to recreate the bug. If you can’t, note what’s inconsistent.

This can be tricky if the bug is intermittent. In such cases, look for patterns. Does it only happen on mobile? Only on Tuesdays? Logging is your best friend here.

I once had a race condition bug involving database writes that only occurred under heavy load. It was ghost hunting. It took extensive logging and analysis to finally reproduce it reliably using artificial delays and load testing tools. But once I could make it fail on demand, fixing it took five minutes.

3. Check the Basics

What to do: Scan for typos, wrong imports, disconnected services, or incorrect environment variables.

It sounds obvious, but we often overlook the simple things because we assume the problem must be complex.

I once had a friend who spent two hours debugging why his frontend requests weren’t reaching the live API. He checked the CORS headers, he checked the token validation, he checked the server logs. He was spiraling. Finally, he realized his laptop had disconnected from the WiFi.

Always check the power cord first. Is the server running? Did you save the file? Are you hitting the right database? A quick sanity check saves you from optimizing a function that isn’t even being called.

4. Trace Layer by Layer

What to do: Start from the top (e.g., frontend/API call) and verify data flows correctly through each layer (e.g., controller → service → database).

Don’t guess where the error is. Follow the data.

• Frontend: Is the payload correct in the Network tab?
• API Controller: Did the request reach the endpoint?
• Service Layer: Is the business logic applying correctly?
• Database: Is the data actually missing or just not being returned?

5. Isolate the Issue

What to do: If the codebase is complex, build a minimal test version (e.g., a single function or API) to rule out dependencies.

If you suspect a library is broken, create a tiny script that only uses that library. If it works there, the issue is in your integration. Isolate the variables until only the bug remains.

6. Note Your Attempts

What to do: If stuck, briefly list what you’ve tried before seeking help.

“Checked layers 1-3, isolated service X, error persists.”

This is crucial when you finally ask for help. It shows you’ve done your homework and prevents others from suggesting things you’ve already tried. It also helps clarify your own thinking—sometimes just writing down the problem is enough to reveal the solution.

Conclusion

Don’t be like a bad manager on yourself. Be like a good mentor: appreciate your efforts, and guide yourself to grow. Remember, you are your own best mentor. Just take a deep breath, step away, and come back to it after a while. You will get it.