Tester-Driven Development
A (usually unintentional) software practice where new requirements emerge through bug reports rather than upfront planning. The testers end up defining the product.
EverydayConcepts.io
Origin
The exact origin is disputed, but the term emerged in the early 2000s agile software community as a deliberate play on Test-Driven Development, itself formalized by Kent Beck in his 2003 book Test Driven Development: By Example. Wikipedia's entry describes it as an anti-pattern — also called "bug-driven development" — where bug reports rather than feature value drive requirements, though practitioners also use the phrase to describe a constructive tester-led workflow.
Updated February 22, 2026