WhatisTDD(Test-DrivenDevelopment)?
Software Development Glossary & Terms
TDD (Test-Driven Development)
Definition.
TDD (Test-Driven Development): A software development process relying on software requirements being converted to test cases before software is fully developed.
In More Detail
Writing the test first forces you to define the expected behaviour before the implementation, which tends to produce smaller, more composable units — largely because code that is hard to test is usually hard to reuse.
In practice I apply it selectively: heavily to business logic, pricing rules, data transformations and anything with edge cases worth pinning down, and lightly to UI layout that changes often. The value of a test is its cost of maintenance measured against the bugs it actually catches.
In Practice
I don't practice strict TDD on every project, but I do write tests for the parts that are expensive to get wrong — payment flows, authentication, and anything touching money or user data get test coverage regardless of the rest of the codebase's approach.
Related Terms
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If you are working out whether this applies to your own project, the case studies show where it turned up in real builds, services lists what I take on, and pricing gives the starting figures.
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