Journeyman OneStream Consultant

MANTECH seeks a motivated, career and customer-oriented Journeyman One Stream Consultant to join our team. This is a REMOTE position.

At MANTECH we are re-engineering the financial backbone of the U.S. Government. We provide highly configured, mission-critical Planning, Programming, Budgeting, and Execution and Financial Close and Reporting solutions leveraging the One Stream platform.

As an One Stream Consultant, you will serve as a technical lead and subject matter expert for our most complex implementations. You will transition from pure building to architecting—designing entire application modules, translating functional requirements into technical blueprints, and guiding a team of associates to deliver high-performance solutions. You will own the technical quality of the application, ensuring performant business rules, streamlined security, and scalable data models.

• Lead the design of application modules (e.g., PPBE, Workforce, Capital, Capex), creating technical specifications that translate functional requirements into scalable One Stream architecture.

• Advanced Development: Write and optimize complex Business Rules of all types (Finance, Parser, Connector, Extender) and design sophisticated Workflow strategies to solve unique client challenges.

• Data Strategy & Integration: Design dynamic data load processes and Custom Tables for complex datasets; create Variance Analyses to validate data integrity between source systems and One Stream.

• Technical Leadership & Mentorship: Parse complex requirements into development tasks for Associate Consultants; conduct code reviews, teach troubleshooting techniques, and support junior staff in resolving helpdesk tickets.

• Market Place & Solutions: Configure and modify Market Place Solutions (e.g., Line Item Modeling, Task Manager, etc.) and integrate them into the core application.

• Reporting Strategy: Design and implement comprehensive reporting strategies using BI Viewer, Extensible Documents, and Cube Views, ensuring optimal performance and usability.

• Consulting Mindset: Listen carefully to what others need (client and team members) and be willing and ready to respond to those needs to the best of your ability; look beyond the “easy” answer working collaboratively to bring the best Mantech has to offer to exceed others’ expectations.

• Bachelor’s degree in Computer Science, Systems Engineering, Information Systems, or related field.

• 5+ years of experience in software development or financial systems implementation.

• 3+ years of dedicated One Stream implementation experience.

• 1+ years of One Stream XF implementation, configuration, and optimization experience

• Advanced proficiency in  or C# and SQL.

• Strong understanding of One Stream architecture, including Data Management, Cube Design, and Security.

• Experience with the federal Planning, Programming, Budgeting, and Execution (PPBE) process or financial management within the government sector.

• Experience assisting with ATOs, Single Sign-On (SSO), or working in a professional services/consulting firm.

• One Stream Certified Professional (OCP).

• Certified Government Financial Manager (CGFM) or Certified Defense Financial Manager (CDFM).

• CompTIA Security+ certification.

• US Citizenship with the ability to obtain a Secret security clearance.

• Must be able to remain in a stationary position 50%

• Frequently communicates with co-workers, management, and customers, which may involve delivering presentations

• Must be able to exchange accurate information in these situations

MANTECH International Corporation considers all qualified applicants for employment without regard to disability or veteran status or any other status protected under any federal, state, or local law or regulation.

If you need a reasonable accommodation to apply for a position with MANTECH, please email us at  and provide your name and contact information.