tdd-london-chicago
About
This skill helps developers apply both London (mock-based) and Chicago (state-based) TDD approaches when practicing test-driven development. It guides style selection based on code type—using Chicago for domain logic and London for external dependencies—while following the red-green-refactor cycle. Key capabilities include generating tests, implementing minimal code, and providing quick reference guidance for each school.
Quick Install
Claude Code
Recommendednpx skills add mattnigh/skills_collection -a claude-code/plugin add https://github.com/mattnigh/skills_collectiongit clone https://github.com/mattnigh/skills_collection.git ~/.claude/skills/tdd-london-chicagoCopy and paste this command in Claude Code to install this skill
GitHub Repository
Frequently asked questions
What is the tdd-london-chicago skill?
tdd-london-chicago is a Claude Skill by mattnigh. Skills package instructions and resources that Claude loads on demand, so Claude can perform tdd-london-chicago-related tasks without extra prompting.
How do I install tdd-london-chicago?
Use the install commands on this page: add tdd-london-chicago to Claude Code as a plugin, or clone its repository into your skills directory, then restart Claude so it picks up the skill.
What category does tdd-london-chicago belong to?
tdd-london-chicago is in the development-practices category, tagged tdd, testing, london-school, chicago-school, red-green-refactor and mocks.
Is tdd-london-chicago free to use?
Yes. tdd-london-chicago is listed on AIMCP and free to install. It runs inside Claude, so no separate service account is required to use the skill itself.
Related Skills
This Claude Skill helps developers apply both London (mock-based) and Chicago (state-based) TDD approaches when practicing test-driven development. It guides you to choose the appropriate style based on your context—using Chicago for domain logic and London for code with external dependencies. The skill follows the red-green-refactor cycle and works with specialized testing agents to generate, implement, and refactor tests.
This Claude Skill applies safe refactoring patterns to improve code structure while preserving existing behavior. It's designed for cleaning up code, reducing technical debt, and enhancing maintainability through a disciplined test-first approach. The skill emphasizes small, incremental changes with continuous testing to ensure reliability during code transformations.
This skill conducts automated code reviews focused on quality, testability, and maintainability, prioritizing critical feedback like bugs and security issues. It's designed for use during code reviews, when providing feedback, or when establishing review practices. The tool categorizes feedback by severity and emphasizes asking questions over issuing commands.
This Claude Skill performs context-driven code reviews focused on code quality, testability, and maintainability. It prioritizes actionable feedback on bugs, security, and design over style preferences, using a structured severity system. Developers should use it when reviewing code, providing feedback, or establishing team review practices.