Senior Data Engineer (OLAP)

Senior Data Engineer (OLAP/Semantic Modelling) | 6 Month Contract | £550-600 p/day | Outside IR35 We’re seeking a highly specialised Data Engineer with deep expertise in OLAP, Tabular, and Multidimensional modelling to join a technology-driven organisation on a long-term contract. If you have strong SSAS, semantic modelling, and Excel cube integration experience — this role is for you. This is a hands-on, onsite position where you’ll architect and optimise analytical models, build high-performance data pipelines, and design robust semantic layers that directly power business-critical reporting and Excel-based analysis. Required Skills: OLAP, Tabular, Semantic Layer Expertise: • Advanced SSAS Tabular & Multidimensional modelling (MUST have) • Proven experience designing semantic layers, calculated measures, perspectives, hierarchies, partitions, aggregation strategies • Strong Power BI semantic model understanding (datasets, relationships, optimisation) • Ability to dynamically load data into Excel using OLAP cubes — essential • Expert in DAX / MDX, cube optimisation, processing strategies Data Engineering & SQL: • Strong expertise with MSSQL Server (schema design, tuning, indexing, profiling) • Advanced SQL and dimensional data modelling (SCDs, fact/dim, conformed dimensions) • Experience with PostgreSQL optimisation. • Advanced Python skills ETL/ELT Pipelines: • Hands-on experience building pipelines using SSIS, dbt, Airflow, or similar • Strong understanding of enterprise ETL frameworks, lineage, and data quality Cloud & Infrastructure: • Experience designing and supporting AWS-based analytical infrastructure • Skilled in working with S3 and integrating cloud sources into data models Key Responsibilities: • Design, build, and maintain OLAP, Tabular, and Multidimensional models used across the business • Develop semantic models and robust data structures for Power BI and Excel cube connectivity • Create and optimise ETL/ELT pipelines integrating data from S3 and diverse source systems • Administer and tune MSSQL Server and PostgreSQL for high performance and reliability • Ensure model scalability, accuracy, consistency, and rapid processing times • Collaborate closely with BI, reporting, and business teams to improve data accessibility and performance • Maintain secure, scalable cloud infrastructure in AWS supporting analytical workloads • Evaluate and introduce new modelling techniques and performance optimisations If you're an OLAP/Tabular Specialist who enjoys complex modelling challenges and building powerful analytical layers that the business relies on daily - we want to speak with you. If this sounds like you, apply now for immediate consideration!