Semantic Architect | Knowledge Graphs | Natural Language Processing | LLM | Ontologies | London, Hybrid

Overview

Semantic Architect | Knowledge Graphs | Natural Language Processing | LLM | Ontologies | London, Hybrid

Mission
We are a growing health-technology company building AI systems that improve how information flows within healthcare organisations.
Our platform combines natural language processing, knowledge graphs, and generative AI to help healthcare providers and payers reduce administrative workload, improve decision-making, and deliver better outcomes.

We are now hiring a Semantic Architect to lead the design and implementation of our graph-integrated generative AI architecture.

This is a senior, hands-on technical leadership role focused on building production-grade AI systems that combine LLMs, NLP pipelines, and structured knowledge.

The Role
You will design and own the architecture that connects:

NLP pipelines processing clinical text
Knowledge graphs and ontologies
LLM reasoning and orchestration layers
Evaluation and benchmarking systems
Your goal is to ensure these components work together as a coherent, reliable, and explainable AI platform suitable for regulated healthcare environments.
You’ll also help scale the Applied AI function by setting technical standards and coordinating complex AI development across engineering teams.

Key Responsibilities
Architecture & Technical Leadership

Design end-to-end AI architectures integrating NLP, LLM orchestration, and knowledge graphs
Define how structured semantics guide and validate generative outputs
Set technical design standards for Applied AI systems
Ensure AI features are robust, production-ready, and aligned with product goals

Applied AI Delivery

Break product requirements into clear technical implementation plans
Coordinate work across NLP, graph engineering, and product teams
Maintain architectural coherence as systems scale

Evaluation & Quality

Design evaluation frameworks for:
hallucination detection
clinical concept extraction accuracy
model regression testing
Implement structured outputs and schema-constrained generation
Introduce human-in-the-loop review and continuous evaluation

Compliance-Aware AI Systems

Build AI workflows with traceability and auditability by default
Ensure systems align with healthcare regulatory requirements across UK and US contexts

Requirements
Core Experience

MSc in Computer Science, AI, or related field (or equivalent experience)
3+ years building production AI systems involving structured knowledge
Strong experience integrating LLMs with knowledge graphs or structured data
Experience building NLP pipelines and semantic reasoning systems

Technical Skills

Python for NLP pipelines, orchestration, and evaluation tooling
Experience with LLM engineering and prompt design using structured outputs
Familiarity with schema-constrained generation (JSON / ontology-driven outputs)
Experience designing evaluation frameworks for production LLM systems

Knowledge Graphs

Experience designing AI systems grounded or validated by graph structures
Ability to collaborate with knowledge engineers on ontology design
Understanding of graph performance and scaling considerations

Nice to Have

Experience in regulated environments (healthcare, fintech, gov, etc.)
Experience integrating AI systems into production services
Interest in building reliable AI systems in high-impact domains

What We’re Looking For

Systems thinker who values clarity and architectural coherence
Pragmatic engineer focused on production impact
Comfortable taking ownership of complex technical systems
Strong communicator who shares and documents architectural knowledge

Hiring Process

Introductory screening interview (30 mins)
Technical deep-dive interview with AI and engineering leadership
Final interview and offer

Benefits

Competitive salary
Company pension
25 days annual leave
Flexible hybrid working
Employee Assistance Programme
Central London office

Semantic Architect | Knowledge Graphs | Natural Language Processing | LLM | Ontologies | London, Hybrid

Company:

Enigma

Qualifications:

Language requirements:

Specific requirements:

Educational level:

Level of experience (years):

Senior (5+ years of experience)

Tagged as: Industry, Natural Language Processing, NLP, Ontologies, United Kingdom