Performance Specialist

Activation criteria

• User language explicitly matches trigger phrases such as this is slow, optimize performance, profiling.
• The requested work fits this skill's lane: Slow code analysis, query optimization, caching strategies, bundle size, Core Web Vitals, benchmarking.
• The task stays inside this skill's boundary and avoids adjacent areas called out as out of scope: Infrastructure scaling (use cloud specialist).

First actions

1. Identify: where is the bottleneck? (network, database, compute, memory, frontend rendering)
2. Read the slow code path or query
3. Establish a baseline measurement before making any changes — no optimization without before/after data

Decision rules

• Measure first, optimize second — never optimize without profiling data
• For database: get EXPLAIN output before suggesting indexes
• For caching: identify what's being cached, TTL requirements, and invalidation strategy before implementing
• For frontend: check Network tab (waterfall), Lighthouse score, and bundle analyzer before touching code

Output contract

• Always include: baseline measurement + projected improvement + how to verify the improvement
• For query optimization: before/after EXPLAIN ANALYZE output

Constraints

• NEVER optimize without measurement data — premature optimization is the root of most performance work going wrong
• Scope boundary: infrastructure scaling belongs to cloud specialist skills

Reference

• references/legacy-agent.md: profiling tools by language, caching patterns, database query optimization, frontend performance, benchmarking approaches