Protegrity

Senior Software Engineer, Ontology & Reasoning Systems (819)

Connecticut · Senior

Sponsorship not specifiedDetected 26 days ago

PythonJavaGoScalaExpressLLMsRAGResearchCollaboration

About the role

In this role, you will formalize complex domains into entities, relationships, constraints, and rules that allow the system to derive conclusions from underlying facts.
A key focus will be making those conclusions explainable and traceable, with clear derivation paths back to the source data and logic that produced them.
LLMs play an important role at the ingestion boundary, supporting extraction, normalization, and categorization of information from unstructured or ambiguous inputs.

Own the ontology and rule layer that unifies structured, semi-structured, and unstructured enterprise data into a single reasoning model.
Model entities, relationships, events, and constraints across heterogeneous sources, and develop rules that derive conclusions from combinations of facts.
Build retrieval capabilities, including vector search, keyword search, and graph traversal, to support reasoning workflows.
Practical experience building LLM-powered systems, including structured extraction, RAG, or classification pipelines, with sound judgment about where model outputs require validation.

5+ years of experience building backend systems in a modern language such as Python, Go, Java, Scala, Rust, or similar, or equivalent practical experience.
The ability to reason about soundness, completeness, and tractability, and to express complex domains as formal rules and constraints.
Hands-on experience with declarative, logic-based, or rule-based reasoning systems such as Datalog, Answer Set Programming, constraint logic programming, Prolog, production rule engines, SMT solvers, or similar.
Deep experience with knowledge graphs and graph data, including RDF, SPARQL, property graphs, or graph databases such as Neo4j.
Experience designing systems whose outputs trace back to their inputs, including provenance, derivation chains, or evidence trails.
Protegrity offers the opportunity to work at the intersection of innovation and collaboration, with the ability to make a meaningful impact on the industry while working alongside some of the brightest minds.

Experience with constraint satisfaction or deductive reasoning, including CSP, unification, fixpoint or closure computation, or constraint propagation.
Experience with formal ontology and semantics, including OWL, SHACL, description logics, or reasoners.
Experience with LLM evaluation, entity resolution, citation validation, or hallucination reduction.
Experience with symbolic computation, theorem proving, model checking, or formal verification.
Should you accept this position, you will be required to consent to and successfully complete a background investigation.
Ensuring a diverse and inclusive workplace is our priority.

We offer a competitive salary and comprehensive benefits with generous vacation and holiday time off.

This listing is sourced directly from Protegrity's careers page and normalized into a canonical job model.