What problem does it solve? Slow applications lose users, but optimizing without measurement wastes effort on the wrong bottlenecks. This Skill enforces a disciplined measure-identify-fix-verify-guard workflow so every performance change is justified by real data and regressions are caught before they ship. ## Core Features & Use Cases - Measurement-First Workflow: Establishes baselines with synthetic tools (Lighthouse, DevTools) and real-user monitoring (web-vitals, CrUX) before touching any code. - Anti-Pattern Fixes: Provides concrete before/after code for N+1 queries, unbounded fetching, connection pool exhaustion, missing image optimization, unnecessary React re-renders, large bundles, and missing caching. - Database Query Analysis: Guides reading EXPLAIN ANALYZE output to decide when indexes help, when they don't, and how to shape composite indexes for the query. - Use Case: Your API's p95 latency spikes after a release. Use this Skill to profile the slow endpoint, discover an N+1 query pattern, fix it with a single joined query, verify the improvement exceeds run-to-run variance, and add a CI performance budget to prevent regression. ## Quick Start Ask the AI to analyze why your page or API endpoint is slow and propose a measured optimization plan following the performance workflow.
