What problem does it solve? Features and bug fixes often ship without adequate test coverage or performance validation, leading to regressions, security holes, and slow pages discovered only in production. This Skill enforces a mandatory quality gate so every behavioral change ships with unit tests and performance checks. ## Core Features & Use Cases - Backend Testing Standards: Defines what to test per layer (API endpoints, auth, data access, validation, rate limiting, security boundaries) with mocking rules and test structure templates. - Frontend Testing Standards: Covers rendering, interactions, form validation, auth gating, XSS prevention, and accessibility for vanilla JS or framework-based UIs. - Performance Gates: Provides concrete checks for API response time (<100ms), payload size, KV operation counts, HTML file size, DOM complexity, and script initialization time. - Use Case: When adding a new API endpoint, the Skill requires happy-path, validation, auth, and edge-case tests plus a response-time check before the feature can be declared complete. ## Quick Start Apply the quality gate to my new feature and make sure all required unit tests and performance checks pass before marking it done.