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docs/content/stories/epic6/6.6-performance-optimization.md

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+# Story 6.6: Performance Optimization
+
+## Metadata
+- **Story ID**: 6.6
+- **Title**: Performance Optimization
+- **Epic**: 6 - Observability & Production Readiness
+- **Status**: Pending
+- **Priority**: Medium
+- **Estimated Time**: 6-8 hours
+- **Dependencies**: 1.2, 5.1
+
+## Goal
+Optimize platform performance through database connection pooling, query optimization, response compression, and caching strategies.
+
+## Description
+This story implements performance optimizations including database connection pooling, query optimization, response compression, and strategic caching.
+
+## Deliverables
+
+### 1. Database Connection Pooling
+- Configure max connections
+- Configure idle timeout
+- Monitor pool stats
+- Connection health checks
+
+### 2. Query Optimization
+- Add indexes for common queries
+- Use database query logging (development)
+- Add slow query detection
+- Query performance monitoring
+
+### 3. Response Compression
+- Gzip middleware for large responses
+- Configurable compression levels
+- Content type filtering
+
+### 4. Caching Strategy
+- Cache frequently accessed data (user permissions, roles)
+- Cache invalidation strategies
+- Cache warming
+
+## Acceptance Criteria
+- [ ] Database connection pooling is optimized
+- [ ] Query performance is improved
+- [ ] Response compression works
+- [ ] Caching strategy is effective
+- [ ] Performance meets SLA (< 100ms p95 for auth endpoints)
+
+## Files to Create/Modify
+- `internal/infra/database/client.go` - Connection pooling
+- `internal/server/middleware.go` - Compression middleware
+- `internal/perm/in_memory_resolver.go` - Add caching
+