Meridian

An AI tutor lives or dies on educator trust. Hand students answers and learning stops; hallucinate and the school walks. Built for California school districts, Meridian had to teach Socratically, stay grounded in the schools' own textbooks, and hold to COPPA-grade compliance for its youngest students.

Two pipelines. A seven-stage ingestion engine turns curriculum PDFs into a knowledge graph — chunked, embedded, deduplicated, linked by prerequisite edges. A five-stage tutor classifies intent, retrieves by triple-source rank fusion, streams a guided response — then an output moderator hunts spoon-feeding and regenerates any answer that gives itself away.

Shipped complete — every contract acceptance criterion delivered: 233 passing tests, 70 cloud resources across two availability zones. Real curricula processed — 834 pages became 822 chunks and 66 linked concepts for $4.66. Per-turn cost landed at $0.002 against a $0.03–0.06 target.