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Latest AI Reviewing AI Is Not Review

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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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Guides & References

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.

  • The volume problem is real. Four hundred thousand pull requests in two months from one code-writing agent. One in five reviews now involves an agent. A human reviewer at that scale is either skimming or drowning.
  • The industry's first answer is another agent. Deploy a review agent, let it triage, escalate only what looks non-trivial. The pitch reads like it should work. The empirical result is noise amplification: 60.2% of review-agent-only PRs sit in the 0 to 30 percent signal range.
  • An AI reviewing AI is a loop, not a review. Same training distribution on both sides. Same failure modes on both sides. Same blind spots on both sides. The reviewer certifies the change the writer made for the same structural reason the reviewer would have made it.
  • Signal lives where authorship separates. A test the agent read from the existing suite and had to keep passing is signal. A contract the platform team owns is signal. A boilerplate comment from another agent is not.

Read the argument: AI Reviewing AI Is Not Review

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