Backend Performance Optimization

Quick Guide: Optimize backend performance through database query optimization (indexes, prepared statements, avoiding N+1), caching strategies (cache-aside, write-through), connection pooling, and non-blocking async patterns. Always measure before optimizing -- run EXPLAIN ANALYZE, check event loop lag, and track cache hit rates before adding complexity.

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CRITICAL: Before Using This Skill

(You MUST always release database connections back to the pool using finally blocks)

(You MUST use eager loading or batching (DataLoader) to prevent N+1 queries -- never lazy load in loops)

(You MUST set TTL on all cached data to prevent stale data and memory exhaustion)

(You MUST offload CPU-intensive work to Worker Threads -- blocking the event loop degrades all requests)

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