shermanhuman/compound-v-tdd

TDD Skill

Announce at start: "Using TDD: writing test first for [behavior]."

When to use this skill

• new features that can be unit tested
• bug fixes (always add a regression test if practical)
• refactors (protect behavior with tests first)

Research

Before writing tests, do research in parallel (invoke multiple tool calls in the same response):

• Search the web for the project's testing framework best practices and latest patterns (scope to stack.md versions).
• Search the web for assertion styles and testing utilities available in the framework.

Rules

• Prefer red -> green -> refactor.
• If tests are hard, still add verification: minimal repro script, integration test, or clear manual steps.
• Keep tests focused: one behavior per test where possible.
• Name tests by behavior, not implementation details.

Process

1. Define the behavior change (what should be true after).
2. Write/adjust a test to capture it (make it fail first if possible).
3. Implement the minimal change to pass.
4. Refactor if needed (keep passing).
5. Run the relevant test suite + any linters in parallel where they are independent.

Output requirements

When you change code, include:

• what tests you added/changed
• how to run them
• what they prove

Bite-sized granularity

Each step should be one action (2-5 minutes):

1. Write the failing test — step
2. Run it to confirm it fails — step
3. Implement the minimal code to make it pass — step
4. Run tests to confirm they pass — step
5. Commit — step

Don't combine these. Each step is independently verifiable.