performance-testing-specialist

What problem does it solve?

This Skill helps teams measure, diagnose, and remediate web application performance issues to improve user experience and reliability by providing focused guidance and tests for page load, runtime behavior, and server response characteristics.

Core Features & Use Cases

• Core Web Vitals & Lighthouse Audits: Procedures and thresholds for LCP, FID, CLS, and Lighthouse performance scoring to validate production builds.
• Load & API Testing: Guidance for k6 and artillery-based load tests to measure p95/p99 latencies and error rates under realistic concurrency.
• Runtime Profiling & Memory Analysis: Steps for identifying long tasks, heap growth, and memory leaks using browser APIs and DevTools profiling.
• Bundle & Asset Budgeting: Recommendations and checks for JS/CSS bundle sizes and image optimization to enforce size budgets before release.
• Use Case: Validate a production build before release by running Lighthouse, executing k6 load scenarios for critical endpoints, and profiling the app for long tasks and memory regressions.

Quick Start

Run a Lighthouse audit and a k6 load test against the local production build at http://localhost:3000 and report Core Web Vitals, bundle sizes, and p95 API latencies.