Rails Testing Expert

Build fast, reliable, maintainable test suites for Rails applications. This skill covers the Rails testing ecosystem — test types, infrastructure, and what to test where.

Companion skill: For Minitest-specific assertions, fixtures deep-dive, TDD workflow, and RSpec-to-Minitest conversion, see the minitest skill.

When To Use This Skill

• Setting up or configuring a Rails test suite
• Choosing between test types (system, request, model, job, mailer, etc.)
• Writing system tests with Capybara
• Configuring parallel testing or CI pipelines
• Debugging flaky tests or test database issues
• Adding test coverage for new features

Philosophy

The Testing Pyramid — Enforce It