Senior Semantic Data Engineer: Ontologies & Knowledge Graphs

Chain IQ; Lisboa; On-site; EUR 70,000 - 110,000; Full time

Benefits offered by this job

Great Place to Work-certified

Job summary

Chain IQ is building an AI-native procurement platform. We are seeking a semantic modelling expert to define ontologies, maintain procurement knowledge graphs, and collaborate with data and product teams to enable retrieval, reasoning, and AI-driven workflows.

You will model business meaning and lifecycle states, ensuring long-term semantic maintainability and interoperability across the platform. Based in Lisbon, you’ll join a global team driving procurement transformations.

Qualifications

• Experience with semantic modelling and ontologies.
• Strong understanding of entities, relationships, events and business context.
• Ability to translate procurement concepts into reusable semantic structures.
• Familiarity with graph databases and knowledge representation.

Responsibilities

• Define and maintain procurement ontologies covering entities, attributes, relationships, events, states, and business concepts.
• Own the semantic model for core domains such as suppliers, contracts, obligations, and sourcing events.
• Design and evolve procurement knowledge graphs representing entities, relationships, dependencies, and business context.
• Define context graph patterns used to assemble relevant information for users, workflows, retrieval systems, and AI agents.
• Model temporal relationships, lifecycle states, provenance, and ownership explicitly.
• Define graph construction patterns linking structured data, documents, and external signals to canonical entities.
• Establish approaches for entity resolution, supplier normalization, deduplication, and relationship confidence.
• Define validation rules and quality expectations for ontology and graph structures.
• Ensure models support retrieval, reasoning, workflow automation, and AI agent execution.
• Collaborate with Data Architecture, Data Engineering, Product, AI, Domain, and Governance teams.
• Help eliminate duplicated business logic by moving meaning into shared semantic assets.

Skills

Semantic modelling

Knowledge graphs

Ontology design

Graph data modelling

Domain modelling

Tools

RDF/OWL

Property graphs

Neo4j/GraphDB

Job description

Chain IQ is building an AI-native procurement platform. We are seeking a semantic modelling expert to define ontologies, maintain procurement knowledge graphs, and collaborate with data and product teams to enable retrieval, reasoning, and AI-driven workflows.

You will model business meaning and lifecycle states, ensuring long-term semantic maintainability and interoperability across the platform. Based in Lisbon, you’ll join a global team driving procurement transformations.