
OneStream Dev/Arch
AerCap
Dublin
Skills:
Compliance
Reporting
AI
Infrastructure
Security
Insurance
Continuous Improvement
Finance
Automation
Excel
Description
Your mission
ESSENTIAL FUNCTIONSÂ
- Partner with finance and business stakeholders to understand requirements and translate them into scalable OneStream solutions
- Lead solution design, ensuring outcomes are robust, maintainable, and aligned to broader architecture and data strategy
- Develop and enhance OneStream applications across core use cases (reporting, planning, forecasting, reconciliations, and tax)
- Provide ongoing application support, troubleshooting issues and continuously improving existing solutions
- Act as a technical lead within the OneStream domain, guiding design decisions and promoting best practices
- Mentor and support junior team members, providing hands-on coaching and knowledge transfer
- Contribute to building internal capability and reducing reliance on external consultants
- Identify opportunities to optimise and evolve the platform, including leveraging new OneStream features and releases
- Proactively explore and apply AI-driven capabilities to improve development efficiency, automation, and business insight
- Drive reduction of technical debt and improve overall solution quality and sustainability
- Collaborate with architecture, infrastructure, data, and other system owners to ensure alignment and manage upstream/downstream impacts
- Support Agile delivery processes, including backlog refinement, estimation, and sprint planning
- Ensure high-quality delivery through structured testing and support for User Acceptance Testing (UAT)
- Manage deployments with appropriate controls, including release planning, runbooks, and hypercare support
- Maintain clear and accurate technical documentation to support knowledge sharing, auditability, and long-term maintainability
- Ensure compliance with organisational, regulatory, and security standards, including SOX requirements
- Stay current with OneStream platform developments, industry best practices, and emerging technologies, continuously bringing forward improvement ideas
Your profile
JOB REQUIREMENTS, QUALIFICATIONS, and COMPETENCIES
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Educational/ Experience
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- Degree in Finance, Business, Information Systems, or a related field
- 5+ yearsâ experience delivering EPM solutions, including hands-on OneStream experience in a delivery or support capacity (implementation or post go-live evolution)
- Proven experience working across core EPM processes (consolidation, reporting, planning, forecasting)
- Strong understanding of the full software development lifecycle (SDLC)
- Experience operating in an Agile delivery environment
Core Competencies
- Strong analytical and problem-solving capability, with the ability to diagnose and resolve complex issues
- Self-starter with high levels of ownership and a proactive approach to identifying and delivering improvements
- Operates effectively as an individual contributor while collaborating closely within a small, high-performing team
- Comfortable operating as a senior member of a small team, providing guidance and support to less experienced developers
- Continuous improvement mindset, with a focus on efficiency, quality, and long-term maintainability
- Adapts quickly to evolving technologies and development frameworks, with a willingness to adopt new approaches (e.g. assemblies, AI-assisted development)
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Technical/Functional
- Strong hands-on experience with OneStream, including business rules, data integration, and applicationevolving development approaches (including assemblies) in a production environment
- Experience with other EPM platforms (e.g. TM1, Oracle, SAP, Tagetik, Adaptive) beneficial, but OneStream expertise strongly preferred
- Proficiency in C# and/or VB.NET /, including development of OneStream business rules development (or similar object-oriented programming)and/or assemblies
- Strong understanding of data models, dimensionality, and performance optimisation within EPM platforms
- Experience designing and building user-facing components (dashboards, forms, reporting interfaces) within OneStream or similar platforms
- Strong Excel skills to support analysis, validation, and user interaction
- Familiarity with source control and structured development practices (e.g. versioning, branching, deployment discipline)
- Strong focus on code quality, maintainability, and reusability
- Experience or interest in using AI-assisted development tools (e.g. Copilot) and exploring AI use cases within finance platforms
Client Relationships
- Builds strong, effective relationships with finance stakeholders, acting as a trusted partner for solution delivery and platform evolution
- Collaborates effectively with internal teams and external partners to deliver outcomes and ensure alignment across systems and processes
- Communicates clearly and concisely with both technical and non-technical audiences
- Operates effectively in a high-demand, fast-paced environment, maintaining a solutions-oriented mindset
- Focused on delivering measurable business value through technology solutions
- Fluent in written and spoken English
What we offer
Benefits
- Medical insurance â Because your health and that of your family is our top priority. Youâre covered!
- Holiday flat in Valencia â Dreaming of sunny days in Spain? Our company flat is ready for your next getaway.
- Gifts for special occasions â We love celebrating you! Expect thoughtful surprises on Easter, Womenâs Day, Fatherâs Day, and more.
- Anniversary gifts â Each work anniversary is a milestone worth celebrating, and weâll continue to mark every year you spend with us with a special gift.
- Team-building events â We value connection beyond work, offering engaging team experiences in great locations to inspire collaboration and fun.
- End of the year celebrations â We wrap up each year with a special celebration, filled with joy, laughter, and unforgettable moments.
- Day off on your birthday â Your special day is yours to enjoy, no work required!
- Monthly massage day â Treat yourself to a relaxing massage at the office once a month.
- Monthly themed lunch â Delicious food and great company â letâs keep sharing laughs and stories around the table each month.
- Community and social initiatives â We bring people together through activities like Bring Kids to the Office Day, donation drives, tree planting, sporting events, decorating the Christmas tree with your colleagues, celebrating new office openings, Principal33âs anniversary, Exchange Office, and more!
- Access to Udemy Learning Platform â We know growth matters, so you now have unlimited access to thousands of courses on Udemy. Develop your skills, anytime, anywhere!
- German Language Courses â We offer dedicated language courses to help you develop your German skills, supporting both personal and professional growth.
- Personal & Professional Growth â We support your development through masterclasses with experienced trainers and are open to investing in courses and training that help you grow.
About Principal33

Principal33