Senior Power BI Developer

We are seeking a talented and experienced Senior Power BI developer to join our team. This is an exciting opportunity to drive the design and delivery of impactful data visualisation and reporting solutions for the firm and its external clients. As a hands-on Power BI expert, you’ll bring deep knowledge of data modelling, DAX, Power Query and visual storytelling plus working knowledge of Azure Data Factory, SQL and Fabric. Exposure to migrating legacy SSRS reports, and multidimensional cubes is a strong advantage. Your technical expertise, combined with a pragmatic approach to implementation and best practices, will be critical to elevating our reporting landscape in a fast-paced, maturing data environment.

Please note, this role can be based either from our London or Cardiff offices.

• Design, develop, and maintain end-to-end engaging Power BI solutions, including semantic models, dashboards and interactive reports.
• Collaborate with business stakeholders to gather requirements and translate them into impactful visual analytics and transactional reports.
• Optimize Power BI semantic models for performance, scalability, and usability.
• Leverage Power Query (M), DAX, and SQL to manipulate and transform data from diverse sources.
• Automate data refreshes and maintain report performance across large datasets.
• Ensure reports adhere to design best practices and usability standards.
• Support and embed Power BI solutions within business workflows and applications (e.g., SharePoint, Teams, PowerApps).
• Ongoing monitoring of latest developments in Analytics and introduction of best practices across the team.

• Provide support for Power BI issues escalated from business users or service desk.
• Liaise with infrastructure/data platform teams to troubleshoot data pipeline and gateway issues.
• Maintain role-based access controls (RBAC) for datasets, reports, and workspaces.
• Ensure high availability of critical dashboards through proactive maintenance and performance tuning.

• Maintain technical documentation covering dataset definitions, data sources, transformation logic, and data lineage.
• Contribute to and enforce Power BI governance standards, including naming conventions, workspace management, and data security.
• Ensure adherence to data governance, GDPR, and regulatory compliance in all Power BI deliverables.
• Ensure traceability of report metrics back to source systems.

You will have a professional manner, excellent communication and interpersonal skills, and have previous experience working within an office. You’ll have a flexible nature and will enjoy working within a fast-paced team, and will be highly organised. You’ll also possess strong numeracy and attention to detail skills, which will be key within this role. We are looking for someone who is passionate about being a team player, who is keen to support others.

• Ideally four+ years of hands-on experience developing enterprise-grade Power BI solutions including PowerBI Report Builder.
• A deep understanding of DAX, Power Query (M), semantic models, and report performance optimization.
• Exposure to SQL and experience with relational databases, data warehouses, or lakehouses.
• Familiarity with the broader Microsoft Power Platform (PowerApps, Power Automate).
• Experience working within Agile delivery environments and using tools like Azure DevOps.
• Good understanding of CI/CD pipelines and deployment automation for Power BI artifacts (preferred).
• Ability to tell a story with data and strong analytics skills.
• Ability to communicate ideas in both technical and user-friendly language.
• Able to conduct research into data management technologies and best practices.
• Highly self-motivated and directed, with keen attention to detail.
• Able to prioritize and execute tasks.
• Experience working in a team-oriented, collaborative environment.

At Lewis Silkin our ethos is simple. We strive to do the best for our clients, our people and the communities in which we operate. We recognise that an inclusive workplace allows for all kinds of ideas and thoughts, a variety of points of view that can trigger discussions or deliver innovative results, and a wide range of versatile skills and expertise. We are proud of the diversity within Lewis Silkin and of our culture that allows people to be themselves at work, ensuring we provide the best possible service to our clients. We are committed to supporting candidates throughout the recruitment process by supporting anyone who requires adjustments, in order to ensure they have the opportunity to perform at their best. All applicants will be considered equally and fairly. If you’d like to request any adjustments throughout the recruitment process, or would like to discuss flexible working patterns, please email the recruitment team in confidence (recruitment@lewissilkin.com).