Our junior developer found a bug senior developers missed for 2 years. Here's how.
https://www.utilizor.com/services/custom-software-development
Last month, our newest junior developer found a bug senior developers had walked past for 2 years.
It was not even a complicated bug. That is what made it strange.
A legacy system we inherited from another agency had a small calculation error in how it handled refunds. It worked fine 95 percent of the time. The other 5 percent, customers were silently refunded a few rupees less than they should have been.
Nobody noticed. Not the original developers. Not two senior developers who worked on that codebase over two years. Not the client, since the amounts were small enough to go unquestioned.
Our junior developer was writing test cases for an unrelated feature. While going through the refund logic, she asked a question nobody had asked in two years.
Why does this calculation round down instead of rounding to the nearest value.
That question led to the discovery. A rounding function was implemented incorrectly from day one, and every senior developer who touched that file afterward assumed it was correct, since it had clearly been there a long time.
This is something we talk about constantly at Utilizor. Experience is valuable, but assumption is dangerous. Even experienced developers can walk past a bug for years simply because they trust code that has survived a long time.
A junior developer brings something seniors sometimes lose. The habit of asking why, instead of assuming something is correct because it is old.
This is exactly why we never let one person review their own code, no matter how senior. Fresh eyes catch what familiar eyes stop seeing.
We fixed it. We notified the client. We refunded the affected customers properly.
The client did not even know there was a problem until we told him. That is the kind of audit we want to be known for.
If your software has been running for years without a second look, there might be something quietly wrong with it too.
Comment AUDIT or send us a DM. We will review your code for free.
Have you ever found a mistake in something everyone assumed was already correct? Tell us.
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