Performance Optimization

Triage skill for performance issues. Routes to the correct sub-tool or reference based on bottleneck type.

Decision Tree

Performance Issue?
├── Database (slow queries, N+1, indexes, pagination)
│   → Invoke database-optimization skill (covers all DB patterns)
├── Frontend (rendering, bundle size, change detection)
│   → ⚠️ MUST READ docs/claude/frontend-patterns.md
│   → Key: OnPush, trackBy, lazy loading, virtual scroll, tree-shaking
├── API/Endpoint (response time, payload, serialization)
│   → ⚠️ MUST READ references/performance-patterns.md (parallel queries, caching, DTOs)
├── Background Jobs (throughput, batch processing)
│   → ⚠️ MUST READ references/performance-patterns.md (bounded parallelism, batch ops)
└── Cross-Service (message bus, eventual consistency)
    → ⚠️ MUST READ references/performance-patterns.md (payload size, idempotency)

Quick Assessment Checklist

1. Identify bottleneck type using decision tree above
2. Measure baseline (response time, query count, bundle size)
3. Route to correct sub-tool or reference
4. Apply patterns from the routed resource
5. Verify improvement against baseline
6. Monitor for regressions

EP-Specific Quick Wins

• Parallel tuple queries: var (a, b) = await (queryA, queryB);
• Eager loading: repo.GetAllAsync(filter, ct, e => e.Related)
• Projections: .Select(e => new { e.Id, e.Name }) instead of full entity
• Full-text search: searchService.Search(q, text, Entity.SearchColumns())
• Batch updates: repo.UpdateManyAsync(items, dismissSendEvent: true, checkDiff: false)
• Paged processing: PageBy(skip, take) at database level

For detailed patterns, profiling commands, and anti-patterns: ⚠️ MUST READ: .claude/skills/arch-performance-optimization/references/performance-patterns.md

Approval Gate

Present findings and optimization plan. Wait for explicit user approval before making changes -- performance optimizations can have wide-reaching side effects.

IMPORTANT Task Planning Notes

• Always plan and break many small todo tasks
• Always add a final review todo task to review the works done at the end to find any fix or enhancement needed