Senior OneStream Developer / Solution Architect

About the role

We are looking for an experienced professional to join our internal EPM team and become a key technical expert for the OneStream platform, taking significant ownership of its technical development and evolution.

We are not looking for a OneStream administrator or someone primarily focused on reporting. We are looking for a technical developer / solution architect with strong hands-on OneStream experience who can independently design, develop, analyse and optimise complex EPM solutions.

You should be comfortable taking over an existing solution, understanding its architecture and codebase, identifying the root causes of issues and driving its further development. Our goal is to build strong OneStream expertise in-house and gradually bring a significant part of the work currently handled by external implementation partners into our internal team.

What you'll do

• Take technical ownership of the OneStream platform: Play a key role in the technical management, development, optimisation and future direction of our OneStream solution.
• Develop in OneStream: Design and develop OneStream Business Rules using VB.NET and/or C#, OneStream API / BRApi and Finance Engine.
• Enhance the existing solution: Analyse and debug our current complex OneStream environment and drive its further development while strengthening our internal capabilities.
• Build and maintain data integrations: Design and develop integrations between source systems and OneStream, working with Data Sources, Connectors, Transformation Rules, Stage, Data Management and Workflow.
• Troubleshoot and optimise: Resolve complex technical and performance issues, perform root-cause analysis and design robust, sustainable solutions.
• Develop the data model: Work with and further develop OneStream's multidimensional data model.
• Support Consolidation and FP&A: Deliver technical solutions supporting Financial Consolidation and Planning / Budgeting / Forecasting processes.
• Develop reporting solutions: Build and optimise Cube Views, Dashboards, Spreadsheet and Table Views, and work with the Excel Add-In.
• Own technical solution design: Translate business requirements from Finance, Controlling and other teams into robust and effective technical solutions.
• Collaborate across teams: Work closely with Finance, Controlling, Tax, IT and external specialists on the ongoing development of the platform.

What we're looking for

• Strong hands-on experience with OneStream development and/or solution architecture.
• Advanced knowledge of OneStream Business Rules and development experience in VB.NET and/or C#.
• Practical experience with OneStream API / BRApi, Finance Engine and multidimensional data modelling.
• Experience with OneStream data integrations, including Data Sources, Connectors, Transformation Rules, Stage, Data Management and Workflow.
• Ability to take ownership of an existing complex OneStream solution, analyse and debug it, and drive its further development.
• Strong troubleshooting and root-cause analysis skills, including experience resolving performance issues.
• Good understanding of EPM processes, particularly Consolidation and Planning / Budgeting / Forecasting.
• Hands-on experience with both Financial Consolidation and FP&A.
• Knowledge of OneStream reporting capabilities, including Cube Views, Dashboards, Spreadsheet, Table Views and Excel Add-In.
• Ability to independently translate business requirements into robust, scalable and maintainable technical solutions.

Nice to have

• Working knowledge of SQL and relational databases.
• Experience with REST APIs, JSON or Smart Integration Connector.
• Knowledge of OneStream security.
• Experience with Git, version control and release management.
• Practical knowledge of IFRS, intercompany eliminations, FX translation, NCI and acquisitions/disposals.
• Experience with Tax Pillar II, CbC, ESG or Long-Term Planning.
• A relevant OneStream certification, such as OneStream Certified Professional (OCP) - Core Platform Architect.

What we offer

• A unique opportunity to become a key member of our internal EPM team and significantly influence the future direction of the OneStream platform across CSG.
• Genuine technical ownership and the opportunity to shape and implement your own solution designs.
• The opportunity to work in a complex enterprise environment on projects spanning multiple companies across the Group.
• Flexible and hybrid working arrangements.
• Competitive compensation and a comprehensive benefits package.
• Opportunities for professional and career development.