Lead Ontology Engineer
GW270
Posted: 28/01/2026
- $200,000-$250,000
- San Francisco, CA
- Permanent
About the job
🧩 Senior Ontology & Knowledge Graph Engineer
We’re hiring a Senior Ontology & Knowledge Graph Engineer to build the semantic backbone behind autonomous systems and complex workflows.
You’ll design ontologies and knowledge graphs that let agents, tools, and models reason, interoperate, and stay consistent as systems evolve.
You’ll work on:
- Ontologies, schemas, and semantic models at system scale
- Knowledge graphs (RDF/OWL, property graphs, hybrid)
- Constraints, typing, and semantic validation
- Integrating messy, real-world data into clean semantic layers
- Supporting reasoning, planning, and ML-driven systems
We’re looking for:
- Strong experience in ontology engineering or knowledge graphs
- Familiarity with RDF/OWL, SPARQL, Neo4j, TigerGraph, or similar
- Comfort bridging symbolic semantics and ML
- High-agency mindset in ambiguous, first-principles environments
- MS required (PhD preferred)
Onsite in San Francisco or Redwood City
Base compensation: 200-250K (base) + equity and other benefits
Kirstie Horsley
Researcher