Ontology and knowledge representation; class hierarchies, relationships, cardinality, inheritance, constraints, taxonomies, and controlled vocabularies; RDF, OWL, SKOS, SHACL, SPARQL, Neo4j/Cypher or comparable semantic and knowledge-graph technologies; SQL, source-data profiling, data mapping, and model validation; ontology governance, lineage, quality metrics, permissions, and auditability; mortgage domain and MISMO knowledge preferred. Enable governed semantic grounding for knowledge graphs, analytics, LLMs, and AI agents with appropriate permissions and auditability.