A bug appears in production.
Your first instinct is often to start changing code immediately.
Add a condition.
Change a query.
Restart the service.
Update a dependency.
Try something else.
Sometimes it works. But you may have no idea why it worked.
That is where debugging becomes dangerous.
The 10-Minute Rule
Before changing the code, spend the first 10 minutes understanding the problem.
Ask:
- What exactly is failing?
- When did it start?
- Can I reproduce it?
- What changed recently?
- Is the problem in the frontend, backend, database, network, or deployment?
- What does the error message actually tell me?
This small habit can save hours.
Stop Guessing. Start With Evidence.
Imagine an API suddenly returns 500.
A junior approach might be:
"The database must be broken."
A better approach is:
- Check the application logs.
- Identify the failing endpoint.
- Check the request parameters.
- Check database connectivity.
- Look at the stack trace.
- Reproduce the request locally.
- Form a hypothesis.
Now you're debugging based on evidence instead of assumptions.
Don't Change Five Things at Once
One of the biggest debugging mistakes is making multiple changes simultaneously.
For example:
- Update the dependency
- Change the SQL query
- Modify the API
- Restart Docker
- Clear the cache
Then the problem disappears.
Great!
But which change fixed it?
You don't know.
Instead, make one controlled change at a time whenever possible.
That gives you something much more valuable than a quick fix:
Understanding.
Read Error Messages Carefully
Error messages are often treated as annoying obstacles.
They shouldn't be.
A good error message can tell you:
- Where the failure happened
- What operation failed
- Which value caused the problem
- Which component reported the error
- Sometimes even what should be fixed
Don't immediately search the entire error message online.
First, understand what it is telling you.
The Real Skill Is Building a Mental Model
Great debugging isn't about memorizing every error.
It's about understanding how your system works.
For example:
User → Browser → API → Service → Database → External API
When something breaks, ask:
"At which point did the expected behavior change?"
That question can dramatically reduce the search area.
Debugging Is Also Communication
In a team, saying:
"The API is broken."
isn't very useful.
Instead:
"The /orders endpoint started returning 500 errors after yesterday's deployment. The request reaches the service successfully, but the database query fails when customer_id is null."
Now another developer can immediately help.
Good debugging produces good information, not just fixes.
Final Thought
The fastest developer isn't always the person who types the fastest.
Sometimes it's the developer who stops typing and starts thinking.
Before changing the code, understand the failure.
Before guessing, collect evidence.
Before applying a fix, understand the cause.
Because a bug that disappears is not necessarily a bug that you solved.
Debug the problem. Don't just silence it.
Sumita
Web Developer