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Latest Agents Should Do TDD: For the Same Reason You Should Have

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Practice TDD with a curated set of real-world katas, each with clear requirements and test cases.

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Learn best practices, naming conventions, and advanced TDD techniques from industry experts.

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Interactive Learning

Discover the TDD Gears model and learn how to apply TDD principles in real-world scenarios.

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Why TDD Matters More in the AI Era

The bar for "good tests" just moved. Agents made it non-optional.

  • TDD's value was always the loop, not the human running it. The procedure pulls code toward correctness, naming, and structure regardless of whose hands are on the keyboard.
  • Vibes-driven generation produces vibes-driven code, fast or slow. Skip the loop and you accumulate features without coherence, whether a human or an agent is doing the typing.
  • Agents are better at the loop than humans ever were. They don't get bored. They don't skip the refactor step at 4 p.m. on Friday. The discipline that was always rare in humans is default in agents.
  • Your job moved up, not away. If the agent runs the loop, you shape the constraints it runs under: vocabulary curation, test API craft, scenario coverage. The discipline didn't disappear. The discipline-bearer changed.

Read the argument: Agents Should Do TDD: For the Same Reason You Should Have

The Bar Moved

Old bar

Tests exist and pass. Good enough for humans with context.

New bar

Scenario names · builders · domain types · ubiquitous language. The test suite is the interface agents operate against.

Rich TDD isn't a style preference anymore. It's infrastructure for compressed-role, AI-augmented teams.

TDD Gears

Shift gears based on context, not habit

TDD Gears model showing Low, Medium, High, and Reverse gears for test-driven development

Low Gear

New territory. Build context. Small steps. Learn the shape of the problem before solving it.

Medium Gear

Patterns emerge. Apply design principles. Let the tests guide you toward better abstractions.

High Gear

Known patterns. Follow existing architecture. Move fast because the structure is already proven.

Reverse Gear

Wrong direction. Back up. Delete the test. Try a different approach. This isn't failure — it's steering.

Learn More About TDD Gears