Job reference:
001262
Salary:
Competitive Day Rate
Location:
All UK Regional Centres
Employment type:
Contract
Directorate:
22 - CDIO - Core
Closing date:
10/11/2026
Role purpose
Own the intellectual core of the prototype: the standard model and the domain-specific programming language used to represent complex rules deterministically. You will also design line graph representations linking source concepts, rules, functions, data, dependencies, decisions and tests.
Why this role is different
This is not a conventional reporting/data-engineering post. We are looking for someone who can move between language design, semantic modelling, standard data architecture and executable software.
What you will do
- Design a standard conceptual and logical model reusable across functions, including concepts, entities, attributes, functions, decisions, inputs/outputs, exceptions, effective periods, evidence, background and versioning.
- Design and prototype a domain-specific language inspired by the qualities of systems such as Catala, DMN, and typed functional languages, while selecting the right implementation approach for this problem.
- Define grammar, abstract syntax tree, type system, identifiers, functions, expressions, precedence, errors, temporal constructs and source annotations.
- Build interpreters, components and deterministic validation/test tooling.
- Design the knowledge/lineage graph model for relationships such as derived-from, depends-on, consumes, produces, supersedes, implemented-by and verified-by.
- Define standard data-to-graph and standard data-to-language transformations, including bidirectional validation where practical.
- Use AI as an engineering accelerator for language/model discovery and transformation, while preventing generated output from bypassing deterministic validation.
- Provide schemas, APIs and versioning conventions that allow SAP and other implementations to consume the standard data representation without owning its semantics.
Essential experience
- Strong data architecture and semantic modelling experience, including standard/logical data models and schema evolution.
- Strong software engineering skills in at least one suitable programming language.
- Hands-on experience with at least one of interpreter construction, DSLs, parsers, ASTs, type systems, formal methods, rules engines or symbolic reasoning.
- Graph modelling experience using property graphs, RDF/OWL or equivalent knowledge-representation approaches.
- Ability to design effective-dated, versioned models with explicit traceability.
- Ability to communicate a rigorous model to AI engineers, enterprise architects and non-technical domain specialists.
Useful differentiators
- Catala or other computational-law/rules-as-code technology.
- ANTLR, tree-sitter, parser combinators or compiler tool chains.
- Neo4j/Cypher, RDF, OWL, SHACL or SPARQL.
- Domain-driven design, event modelling or ontology engineering.
- Generating visual dependency/lineage views from graph or semantic models.
Take a look around the company
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