Intent Engine is a privacy-first, intent-driven system for intelligent search and ad matching. Extracts structured intent from queries with no user tracking. All processing is on-device with automatic session cleanup. Features: • 30ms intent extraction • Privacy-preserving ad matching with fairness validation • Campaign management, A/B testing & fraud detection • GDPR-ready with differential privacy • FastAPI + Redis + PostgreSQL • Scales to 1,100 req/s with 3 replicas