5 posts tagged “tdd”
2026
First run the tests
Automated tests are no longer optional when working with coding agents.
The old excuses for not writing them - that they're time consuming and expensive to constantly rewrite while a codebase is rapidly evolving - no longer hold when an agent can knock them into shape in just a few minutes.
They're also vital for ensuring AI-generated code does what it claims to do. If the code has never been executed it's pure luck if it actually works when deployed to production. [... 355 words]
Red/green TDD
"Use red/green TDD" is a pleasingly succinct way to get better results out of a coding agent.
TDD stands for Test Driven Development. It's a programming style where you ensure every piece of code you write is accompanied by automated tests that demonstrate the code works.
The most disciplined form of TDD is test-first development. You write the automated tests first, confirm that they fail, then iterate on the implementation until the tests pass. [... 279 words]
2025
We find that Claude is really good at test driven development, so we often ask Claude to write tests first and then ask Claude to iterate against the tests.
— Catherine Wu, Anthropic
2009
Test-Driven Heresy. Tim Bray advocates TDD for maintenance development, but argues that it may not be as useful during the exploratory, greenfield development phase of a project.
2007
I don't do test driven development. I do stupidity driven testing... I wait until I do something stupid, and then write tests to avoid doing it again.