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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Ontology Engineer - Expert - **Company:** CCS, LLC - **Location:** Herndon, VA, United States - **Salary:** $220,000.0 - $250,000.0 - **Contract:** Permanent contract - **Skills:** Artificial Intelligence, Data Architecture, Data Integration, Decision Support Systems, Graph Database, Interoperability, Knowledge Management, Machine Learning, Web Ontology Language, Resource Description Framework (RDF), Semantic Web, Software Engineering, Software Systems, SPARQL, Knowledge Representation, Data Management, Machine Learning Operations, Software Version Control - **Published:** July 3, 2026 - **Apply:** https://www.clearancejobs.com/jobs/9028077/ontology-engineer-expert ## About the Role TS/SCI clearance with CI polygraph or willingness to take one Full-Time, W-2 Employment 15+ years of relevant professional experience for Expert Bachelor's degree in Software Engineering or related discipline. Current / active TS/SCI clearance with CI polygraph or willingness to take one. Background investigation required, including a minimum of a criminal and credit check as well as at least three professional references., * Must be a US citizen and have an active TS/SCI with CI poly. * 12 years of experience and an advanced degree or 15+ years of experience with a bachelor's degree. * Demonstrated experience designing and implementing ontologies, taxonomies, or knowledge graphs in operational or research environments. * Experience applying Semantic Web technologies, including RDF, OWL, and SPARQL. * Knowledge of ontology engineering methodologies, data modeling principles, and semantic interoperability frameworks. * Ability to communicate complex technical concepts effectively to both technical and non-technical stakeholders. An Excellent Candidate for this position will meet most of the following experience requirements: * Experience developing and maintaining enterprise knowledge graphs and integrating heterogeneous data sources. * Familiarity with AI/ML workflows and the use of ontologies to improve model explainability, reasoning, and decision support. * Experience providing technical leadership, mentoring, and formal knowledge transfer to Government personnel or large multidisciplinary teams. * Certified Data Management Professional (CDMP) or equivalent data architecture certification. * Certified Knowledge Manager (CKM) or comparable knowledge management credential. * Formal training or certification in Semantic Web technologies, knowledge graphs, ontology engineering, RDF, OWL, or SPARQL. General personal traits we know will connect well with the team: * Superior communication skills * A positive, willing attitude * An ability to think on your feet and solve problems quickly * Adaptability to learn new methodologies and technologies * Comfortable working in an agile team environment * Technology and methodology agnostic, but accepts using tools needed for the requirement * Enjoys coaching and teaching ## Description Client is seeking a Ontology Engineer to is seeking an Ontology Lead to join our team. In this position you will design, develop, and maintain domain-specific ontologies and knowledge models in support of Object Based Intelligence (OBI) mission requirements. The Lead Ontologist serves as the technical authority for the design, development, and maintenance of domain-specific ontologies and knowledge models that support Object-Based Intelligence (OBI) mission requirements. This position applies semantic technologies and knowledge representation methodologies to enable data interoperability, advanced analytics, and knowledge integration across diverse data sources and object-management systems. Leveraging Semantic Web standards, including RDF, OWL, and SPARQL, the Lead Ontologist develops scalable knowledge frameworks that enhance data discoverability, support AI/ML applications, and facilitate effective knowledge transfer to Government stakeholders. As an Ontology Engineer , you will be a vital part of our team, contributing to the design and implementation of advanced software solutions. You will work under the guidance of senior engineers to develop your skills and gain hands-on experience in various aspects of software development. This team is building innovative software using mathematical solutions to support users in the defense and intelligence communities. These positions are ideal for both recent graduates and experienced individuals in the software engineering field, they offer a chance to grow and explore different technologies within a dynamic AI-driven environment. Principal Responsibilities: * In coordination with domain experts, design, develop, and maintain domain-specific ontologies, taxonomies, and knowledge graphs that support Object-Based Intelligence mission objectives. * Apply Semantic Web standards and technologies, including RDF, OWL, SHACL, and SPARQL, to model, represent, and query complex data relationships. * Establish and maintain semantic data integration frameworks that enable interoperability across internal and external object-management systems. * Collaborate with analysts, data scientists, engineers, and Government stakeholders to capture requirements and translate mission needs into formal knowledge models. * Develop and maintain ontology governance processes, standards, documentation, and version control practices to ensure consistency and scalability. * Support AI/ML initiatives by providing structured knowledge representations that enhance model explainability, interpretability, and contextual reasoning. * Conduct ontology validation, testing, and quality assurance activities to ensure accuracy, completeness, and alignment with mission requirements. * Provide technical leadership, mentoring, and knowledge transfer activities to Government personnel and project team members on ontology development methodologies and semantic technologies. ## Related Videos - [New AI-Centric SDLC: Rethinking Software Development with Knowledge Graphs](https://www.wearedevelopers.com/videos/1417-new-ai-centric-sdlc-rethinking-software-development-with-knowledge-graphs) - [WebMCP - Making Agents a First-Class Citizen of the Web - Andre Cipriani Bandarra & François Beaufort](https://www.wearedevelopers.com/videos/1811-webmcp-making-agents-a-first-class-citizen-of-the-web-andre-cipriani-bandarra-francois-beaufort) - [Putting the Graph In GraphQL With The Neo4j GraphQL Library](https://www.wearedevelopers.com/videos/257-putting-the-graph-in-graphql-with-the-neo4j-graphql-library) - [Context Graphs for Explainable, Decision-Aware AI Agents](https://www.wearedevelopers.com/videos/100318-context-graphs-for-explainable-decision-aware-ai-agents) - [Your organization as a Graph](https://www.wearedevelopers.com/videos/2051-your-organization-as-a-graph) - [Graphs and RAGs Everywhere... But What Are They? - Andreas Kollegger - Neo4j](https://www.wearedevelopers.com/videos/1311-graphs-and-rags-everywhere-but-what-are-they-andreas-kollegger-neo4j) ## Related Articles - [Graph and AI Trends 2026: Why Is AI Running but Not Yet Delivering?](https://www.wearedevelopers.com/magazine/680-graph-and-ai-trends-2026-why-is-ai-running-but-not-yet-delivering) - [Everything a Developer Needs to Know About MCP with Neo4j](https://www.wearedevelopers.com/magazine/604-everything-a-developer-needs-to-know-about-mcp-with-neo4j) - [Coffee with Developers - Maria Apazoglou - Making AI understandable for all in production](https://www.wearedevelopers.com/magazine/475-coffee-with-developers-maria-apazoglou-making-ai-understandable-for-all-in-production) - [Résumé-Driven Development: How IT trends affect the job market for software developers](https://www.wearedevelopers.com/magazine/59-resume-driven-development-how-it-trends-affect-the-job-market-for-software-developers) - [Best US AI Conferences for CTOs in 2026: Build vs. Buy, Vendor Evaluation, and Peer Intelligence](https://www.wearedevelopers.com/magazine/736-best-us-ai-conferences-for-ctos-in-2026-build-vs-buy-vendor-evaluation-and-peer-intelligence) - [Is Software Engineering Over-Saturated?](https://www.wearedevelopers.com/magazine/418-is-software-engineering-over-saturated)