Software Systems Engineer

Leidos is dedicated to making the world a safer place. This starts with helping our customers in the Defense Industry achieve their critical missions. Our dedicated Defense Group employees are solving critical challenges across the globe. At Leidos, we deliver innovative solutions through the efforts of our diverse and talented people who are dedicated to our customers’ success. We empower our teams, contribute to our communities, and operate sustainably. Everything we do is built on a commitment to do the right thing for our customers, our people, and our community. Our Mission, Vision, and Values guide the way we do business. With offices across the United States engaging in the defense, space, cyber and commercial fields, Leidos provides responsive, cost-effective engineering, scientific and IT solutions. Leidos is well known for our people-oriented culture, positive work environment, technical excellence, and resilient business ethics. We are seeking a highly motivated and detail-oriented Software Systems Engineer to support complex defense and government programs throughout the systems engineering lifecycle. The ideal candidate will have strong defense industry experience, expertise in requirements development and management, and hands-on experience with Model-Based Systems Engineering (MBSE) methodologies and tools including Cameo and Jama. This role requires collaboration with cross-functional engineering teams, program leadership, and government stakeholders to support system design, development, integration, verification, and delivery. Primary Responsibilities Perform systems engineering activities across the full system lifecycle including: Requirements analysis Functional decomposition System architecture development Integration & Test Verification & Validation (V&V) Configuration management Risk management Develop, analyze, and maintain system engineering documentation including: Program Interface Documents (PIDs) Interface Control Documents (ICDs) System/Subsystem Specifications (SSS) Software Requirements Specifications (SRS) Support requirements decomposition, allocation, traceability, and change management activities. Utilize Jama for requirements management, traceability, and collaboration across engineering teams. Utilize Cameo Systems Modeler to develop and maintain MBSE artifacts and system models. Support requirements decomposition, allocation, traceability, and change management activities. Develop SysML diagrams including Activity diagrams Sequence diagrams Use case diagrams Interface models Support model-based architecture development and interface definition activities. Conduct technical reviews, requirements reviews, and design reviews with internal teams. Collaborate with software, hardware, cybersecurity, integration, and test teams to ensure system performance and compliance. Provide technical leadership and support cross-functional collaboration across program teams. Ensure engineering products comply with customer requirements, program objectives, and industry standards. Participate in risk identification, mitigation planning, and technical issue resolution Required Qualifications Be a US citizen with ability to obtain a security clearance Bachelor’s degree in Systems Engineering, Electrical Engineering, Computer Engineering, Software Engineering, or related technical field. 4+ years of systems engineering experience or 2+ years with MS degree. Prior experience supporting defense industry or Department of Defense (DoD) programs. Hands-on MBSE experience using Cameo Systems Modeler. Experience with model-based architecture development and SysML modeling. Experience using Jama for requirements management and traceability. Strong experience in requirements development and management. Experience developing and maintaining: Program Interface Documents (PIDs) Interface Control Documents (ICDs) System/Subsystem Specifications (SSS) Software Requirements Specifications (SRS) Experience with: Requirements analysis Functional decomposition System architecture development Verification & Validation (V&V) Integration & Test Configuration management Risk management Familiarity with Jira and Confluence collaboration tools. If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 — and moving faster than anyone else dares. Original Posting: June 26, 2026 For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above. Pay Range: Pay Range $87,100.00 - $157,450.00 The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law. Leidos Leidos is an industry and technology leader serving government and commercial customers with smarter, more efficient digital and mission innovations. Headquartered in Reston, Virginia, with 47,000 global employees, Leidos reported annual revenues of approximately $17.2 billion for the fiscal year ended January 2, 2026. For more information, visit Pay and Benefits Pay and benefits are fundamental to any career decision. That's why we craft compensation packages that reflect the importance of the work we do for our customers. Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and Retirement. More details are available here. Securing Your Data Leidos will never ask you to provide payment-related information at any part of the employment application process. And Leidos will communicate with you only through emails that are sent from a Leidos.com email address. If you receive an email purporting to be from Leidos that asks for payment-related information or any other personal information, please report the email to View email address on click.appcast.io. Commitment and Diversity All qualified applicants will receive consideration for employment without regard to sex, race, ethnicity, age, national origin, citizenship, religion, physical or mental disability, medical condition, genetic information, pregnancy, family structure, marital status, ancestry, domestic partner status, sexual orientation, gender identity or expression, veteran or military status, or any other basis prohibited by law. Leidos will also consider for employment qualified applicants with criminal histories consistent with relevant laws.