Regression
A previously working behavior that breaks after a change.
Plain English
A new change broke something that used to work.
In context
A regression is an unintended loss of existing functionality introduced by code configuration or dependency changes.
Example
“The latest release introduced a regression in file uploads.”
When you'll hear this
- testing
- release review
- incident response
Common misunderstanding
A newly discovered old bug is not necessarily a regression.
Commonly used by
Related terms
Updated: 2026-08-25
