How does this skill handle over-engineering?

It enforces the 'Green' phase requirement of writing only the minimal code necessary to pass the current failing test, adhering to YAGNI (You Ain't Gonna Need It) principles.

When is it acceptable to skip TDD with this skill?

TDD can be skipped for throwaway prototypes, generated code, or configuration files, typically after consulting with a human partner to ensure the shortcut is justified.

What is the 'Iron Law' in this TDD skill?

The Iron Law dictates that no production code should be written until a failing test has been established and verified to fail for the correct reason.

Why is 'Verify Red' a mandatory step?

Watching a test fail proves that the test is actually testing the intended behavior and is capable of catching bugs, rather than passing by accident or due to unrelated logic.

Does this skill support existing codebases?

Yes, it is highly effective for fixing bugs in existing code by first writing a reproduction test or for refactoring legacy code while maintaining existing behavior.

Test-Driven Development (TDD)

Name: Test-Driven Development (TDD)
Author: vgeshel

byvgeshel

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보안 및 테스팅

Enforces a rigorous Red-Green-Refactor workflow to ensure high-quality, verified production code through test-first implementation.

The Test-Driven Development (TDD) skill transforms Claude into a disciplined coding partner that adheres to the strict 'Iron Law' of software engineering: no production code is written without a preceding failing test. By guiding users through the Red-Green-Refactor cycle, this skill helps prevent regressions, documents intended behavior through assertions, and ensures that every line of code serves a specific, verified purpose. It is ideal for developers seeking to reduce technical debt, improve system architecture, and maintain high confidence in their codebase during feature development or bug fixes.

주요 기능

01Supports bug reproduction and regression testing workflows

02Prevents over-engineering by focusing on minimal code implementation

03Provides clear criteria for writing minimal and intent-focused tests

041 GitHub stars

05Enforces the 'Iron Law' of no production code without a failing test

06Guides the mandatory Red-Green-Refactor cycle with verification steps

사용 사례

01Reproducing and fixing bugs by establishing a failing test case first

02Refactoring existing codebases while ensuring no functional regressions

03Implementing new features with high reliability and documented behavior

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add vgeshel/local-skills test-driven-development

For use in Claude.ai and ChatGPT

Download Skill