tdd

Guide test-first feature delivery with a red-green-refactor workflow.

Updated Jan 30, 2026
One-click install
npx skills add https://github.com/Rayzerrek/dotfiles --skill tdd-rayzerrek
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: tdd
Source: https://github.com/Rayzerrek/dotfiles/tree/main/.agents/skills/tdd
Command: npx skills add https://github.com/Rayzerrek/dotfiles --skill tdd-rayzerrek

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

This Skill helps you build features and fix bugs with test-driven development, so you can validate behavior early, keep implementation changes safe, and avoid brittle tests.

Core Features & Use Cases

  • Behavior-first testing: Write tests that describe what the system does through public interfaces instead of how it is built.
  • Red-green-refactor workflow: Progress one behavior at a time with a failing test, minimal code to pass, and cleanup only after the tests are green.
  • Practical testing guidance: Choose integration-style tests, decide what to mock at system boundaries, and shape interfaces for testability.
  • Use case: When adding a checkout flow or fixing a regression, this Skill helps you define the right behaviors to test, implement them incrementally, and refactor confidently afterward.

Quick Start

Ask me to plan and implement one user-visible behavior at a time using test-driven development, starting with the first test and the simplest code needed to make it pass.

Frequently Asked Questions about tdd

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I implement test-driven development for a new feature?▼

To implement test-driven development, you progress one behavior at a time using a red-green-refactor workflow: write a failing test, add minimal code to pass it, and refactor only after the tests are green.

What is behavior-focused test design in TDD?▼

Behavior-focused test design in TDD describes what a system does through its public interfaces, avoiding brittle tests tied to internal implementation details and ensuring safer refactoring.

How do I handle mocking when writing integration tests?▼

When writing integration tests, you should limit mocking strictly to system boundaries, which shapes interfaces for testability while allowing internal components to be verified through integration-style tests.

When should I use vertical slicing in test-driven development?▼

Vertical slicing in test-driven development is used when adding features or fixing regressions, allowing you to plan and implement one user-visible behavior at a time through the full stack.

When should I refactor code during a red-green-refactor cycle?▼

You should refactor code during the red-green-refactor cycle only after the tests are green, ensuring that implementation changes remain safe and the previously validated behavior stays intact.