Location: Hybrid role based in South Wales
Contract Length: Initial 3–6 months (extension likely)
Day Rate: £400 per day (Outside IR35)
Role OverviewWe are seeking an experienced Power BI Specialist contractor to own enterprise semantic modelling, advanced DAX development and reportingernance.This is a hands‑on technical role focused on Power BI semantic models, not dashboard production. You will design, optimise andern certified enterprise datasets built on the Gold data layer, enabling analysts to self‑serve confidently while protecting core business logic.
Key ResponsibilitiesEnterprise Semantic Modelling
1. Design, build and maintain enterprise Power BI semantic models using star schema and dimensional modelling best practice.
2. Develop advanced DAX measures, calculation groups and reusable logic
3. Ensure datasets reflect authoritative, agreed business definitions
4. Implement time‑aware models, surrogate keys and conformed dimensions
Performance & Optimisation
5. Diagnose and resolve performance issues across large andplex models
6. Optimise models through:Measure refactoringCardinality reductionRelationship and filter‑direction optimisation
7. Advise on Import, DirectQuery andposite storage strategies
8. Certify and endorse enterprise semantic models
9. Enforce separation between certified datasets and exploratory/self‑service reporting
10. Prevent duplication of KPIs, measures and business logic
11. Define and embed dataset lifecycle and workspace standards