Power BI Specialist

Location: Hybrid role based in South WalesContract Length: Initial 3-6 months (extension likely)Day Rate: £400 per day (Outside IR35)

Role Overview We are seeking an experienced Power BI Specialist contractor to own enterprise semantic modelling, advanced DAX development and reporting governance.This is a hands-on technical role focused on Power BI semantic models, not dashboard production. You will design, optimise and govern certified enterprise datasets built on the Gold data layer, enabling analysts to self-serve confidently while protecting core business logic.

Key Responsibilities Enterprise Semantic Modelling

• Design, build and maintain enterprise Power BI semantic models using star schema and dimensional modelling best practice.
• Develop advanced DAX measures, calculation groups and reusable logic
• Ensure datasets reflect authoritative, agreed business definitions
• Implement time-aware models, surrogate keys and conformed dimensions

Performance & Optimisation

• Diagnose and resolve performance issues across large and complex models
• Optimise models through:
  • Measure refactoring
  • Cardinality reduction
  • Relationship and filter-direction optimisation
• Advise on Import, DirectQuery and Composite storage strategies

Governance & Hybrid Model Operation

• Certify and endorse enterprise semantic models
• Enforce separation between certified datasets and exploratory/self-service reporting
• Prevent duplication of KPIs, measures and business logic
• Define and embed dataset lifecycle and workspace standards

What you need to do now If you're interested in this role, click 'apply now' to forward an up-to-date copy of your CV, or call us now.If this job isn't quite right for you, but you are looking for a new position, please contact us for a confidential discussion about your career.

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