Semantic/Ontology Engineer

Job Description: We are hiring a Senior Semantic Engineer / Ontology Engineer to lead the design of healthcare-grade ontologies and semantic layers that power trusted analytics, interoperable data products, and AI-ready knowledge systems. You will apply metrics-first semantic modeling and ontology engineering practices aligned to the principles such as clear semantics, reusable meaning, governance-by-design, and measurable business outcomes. You’ll work across RDF and property graph paradigms and Snowflake semantic layer. What You’ll Do • Design and evolve healthcare ontologies and semantic models to standardize meaning across domains (clinical, patient, provider, claims, access, quality, outcomes). • Design data products that are AI-ready and leverage ontologies and semantic models • Build metrics-first semantic layers: • Define canonical metric definitions, dimensions, hierarchies, and calculation rules. • Ensure metrics are explainable, auditable, and consistently implemented across products and teams. • Model knowledge in both: • RDF (RDFS/OWL) for formal semantics and interoperability. • Property graphs for traversal-heavy use cases and relationship analytics. • Develop and maintain semantic artifacts: • Concept schemes, entity models, vocabularies, mappings, and documentation. • Alignment patterns between ontologies, data products, and downstream analytics/AI use cases. • Implement semantic integration patterns: • Entity identity resolution, entity linking, terminology harmonization, and enrichment workflows. • Partner with platform teams to operationalize semantics in Snowflake: • Enable semantic access patterns that support analytics and AI applications. • Contribute to solutions that leverage Snowflake Cortex for semantic enrichment and assisted discovery (within established governance constraints). • Collaborate with governance and architecture stakeholders to embed: • Versioning, stewardship workflows, quality checks, and change management for semantic assets. • Guide best practices and mentor engineers/analysts on ontology engineering, graph modeling, and metrics-first design. Required Qualifications • 8+ years in semantic engineering, ontology engineering, knowledge graph development, or closely related roles. • Demonstrated experience in healthcare data domains (payer/provider, clinical, claims, RWE, quality, outcomes, etc.). • Strong hands-on ontology engineering experience: • RDF, RDFS, OWL • SPARQL and/or graph query experience • Ontology modularization, alignment, and lifecycle management • Experience with property graph modeling (e.g., Neo4j-style patterns) and translating between RDF and property graph representations when needed. • Proven delivery of a metrics-first approach: • Canonical KPIs/metrics definitions, dimensional modeling alignment, semantic consistency across BI and data products. • Experience working with modern cloud data platforms, especially Snowflake, and exposure to Snowflake Cortex for AI-enabled workflows. • Strong stakeholder communication skills: able to translate clinical/business intent into precise semantic definitions and usable artifacts. Preferred Qualifications • Familiarity with healthcare interoperability and terminology standards (e.g., HL7/FHIR, SNOMED CT, LOINC, ICD-10) and how to map/align them to enterprise semantics. • Experience with semantic tooling and practices, validation rules, ontology testing, and CI/CD for semantic assets. • Experience deploying semantic context layers