Senior Semantic Engineer — Ontologies, Knowledge Graphs, AI

Vizient; Chicago (IL); On-site; USD 102,000 - 179,000; Full time

Job summary

Vizient seeks a seasoned data/knowledge engineer to develop and maintain semantic ontologies and models that enable high-quality, interoperable data across the organization. You will translate business concepts into scalable semantic structures, support knowledge graph initiatives, and ensure semantic assets are governed, validated and production-ready for AI-enabled solutions.

You will collaborate with product, data, and business teams to align semantic representations with enterprise data

Qualifications

• Relevant degree preferred.
• 5+ years of relevant experience required.
• Hands-on knowledge of Semantic Web standards and technologies (RDF, OWL, SKOS, SPARQL, SHACL).
• Experience with graph databases and/or triplestores, including semantic modeling, schema design, and query performance in production.
• Experience integrating disparate datasets through common vocabularies, semantic-to-data mapping, and validation.
• Proficiency with ontology development tools and workflows such as Protégé, TopBraid, PoolParty, Stardog.
• Experience applying foundational/top-level ontologies and standards (e.g., BFO, DOLCE, Common Core Ontologies, OBO Foundry).
• Working knowledge of Python, Java, or similar languages for automation and pipeline integration.
• Experience applying software engineering practices to semantic assets (Git, reviews, automated validation/testing, CI/CD).
• Strong analytical, problem-solving, and communication skills for explaining complex concepts.

Responsibilities

• Design, develop, and maintain ontologies, vocabularies, and semantic models aligned with analytics and AI needs.
• Translate client use cases into semantic requirements and implementable models.
• Collaborate with SMEs and technical teams to refine concepts, relationships, and standards.
• Support knowledge graph development and integration with enterprise data platforms, including SPARQL and data mapping.
• Perform validation and quality control to ensure accuracy and interoperability of assets.
• Manage ontology changes via version control, reviews, testing, documentation, and releases.
• Develop and maintain ontology documentation, patterns, standards, and usage guidance.
• Partner with data engineering, platform, product, analytics, and AI teams to align knowledge representation with systems.
• Apply foundational ontologies and standards to enterprise use cases focusing on scalability and usability.
• Develop automation, testing, and semantic pipeline integrations using scripting and software engineering practices.

Skills

Semantic Web standards

RDF

OWL

SPARQL

SHACL

Graph databases

Protégé

TopBraid

PoolParty

Stardog

BFO

DOLCE

Common Core Ontologies

OBO Foundry

Python

Java

Git-based version control

CI/CD

Analytical skills

Communication skills

Education

Relevant degree

Tools

Protégé

TopBraid

PoolParty

Stardog

Job description

Vizient seeks a seasoned data/knowledge engineer to develop and maintain semantic ontologies and models that enable high-quality, interoperable data across the organization. You will translate business concepts into scalable semantic structures, support knowledge graph initiatives, and ensure semantic assets are governed, validated and production-ready for AI-enabled solutions.

You will collaborate with product, data, and business teams to align semantic representations with enterprise data