Location: Hybrid role based in South Wales
Contract 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 dimensionsPerformance & 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 strategiesGovernance & 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 standardsWhat you need to do now
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