Why does it write tests before implementation?

Writing tests first ensures requirements are clearly defined and guarantees that the tests are actually capable of catching failures before implementation begins.

How does the autonomous iteration work?

The skill utilizes a scratchpad and 'grind' pattern to monitor test results and automatically adjust the implementation until all test cases pass.

Can I use this for refactoring existing code?

Yes, it is highly effective for refactoring. You can write tests for existing behavior first to ensure that your refactor doesn't introduce any breaking changes.

Does this skill support any specific testing framework?

While optimized for modern TypeScript environments and Vitest, the workflow is designed to be compatible with any CLI-based test runner available in your environment.

TDD Workflow

Name: TDD Workflow
Author: harlan-zw

byharlan-zw

•

Security & Testing

Implements a rigorous test-driven development cycle by writing failing tests before coding the implementation.

About

This skill enables a structured Test-Driven Development (TDD) workflow within Claude Code, ensuring high code quality and reliability. It guides the AI through a three-phase 'grind' pattern: initializing a scratchpad to track progress, writing comprehensive test cases that fail initially, and iteratively writing the minimal code required to pass those tests. By enforcing a strict separation between testing and implementation phases, it prevents regressions and ensures that every feature is verified against its expected behavior before completion.

Key Features

Automated three-phase TDD workflow: Test, Implement, Refactor
Support for separate commits for tests and implementation code
Strict enforcement of failing tests before implementation begins
2 GitHub stars
Integration with local test runners for real-time verification
Persistent scratchpad tracking for autonomous progress monitoring

Use Cases

Implementing new features based on specific input/output requirements
Refactoring complex legacy codebases with safety nets
Developing critical business logic where zero-regression is mandatory

About

Key Features

Automated three-phase TDD workflow: Test, Implement, Refactor
Support for separate commits for tests and implementation code
Strict enforcement of failing tests before implementation begins
2 GitHub stars
Integration with local test runners for real-time verification
Persistent scratchpad tracking for autonomous progress monitoring

Use Cases

Implementing new features based on specific input/output requirements
Refactoring complex legacy codebases with safety nets
Developing critical business logic where zero-regression is mandatory