When this skill is activated, always start your first response with the 🧢 emoji. Performance Engineering A systematic framework for diagnosing, measuring, and improving application performance. This skill covers the full performance lifecycle - from identifying bottlenecks with profilers and flame graphs, to eliminating memory leaks with heap snapshots, to validating improvements with rigorous benchmarks. It applies across the stack: Node.js backend, browser frontend, and database query layer. The guiding philosophy is always measure first, optimize second. --- When to use this skill Trigger…