Principal Systems Engineer

About Leidos

Leidos is a FORTUNE 500® company bringing a mix of innovative technology and sector expertise to customers in the national security, engineering, and health industries. We deliver innovative solutions through the efforts of our diverse and talented people who are dedicated to our customers' success. Guided by our Mission, Vision, and Values, Leidos empowers its teams, contributes to its communities, and operates sustainably—always with a commitment to doing the right thing for our customers, our people, and our community.

The Leidos Intel Sector combines technology-enabled services and mission software capabilities in the areas of cyber, logistics, security operations, and decision analytics to support Intelligence Community customers as they address evolving national security challenges.

About the Opportunity

Leidos is seeking a Principal Systems Engineer to provide technical leadership and engineering direction across the requirements, architecture, design, integration, verification, and lifecycle management of complex mission systems.

You will guide systems-engineering efforts from stakeholder needs and requirements through architecture, design, integration, verification, deployment, and operations. At this level, you will also provide technical direction across complex hardware/software systems, evaluate and recommend engineering alternatives, maintain technical baselines and configuration integrity, influence system standards and integration strategies, and help guide critical technical decisions.

This role requires extensive systems-engineering experience and demonstrated success planning and leading Systems Engineering efforts.

Why This Role Matters

Complex mission systems require technical leadership that extends beyond individual engineering activities. Requirements, architectures, interfaces, risks, configurations, standards, and lifecycle decisions must remain aligned across interconnected hardware and software components and multiple engineering disciplines.

As a Principal Systems Engineer, you will bring the technical judgment and systems perspective needed to guide those decisions, maintain engineering integrity, and help ensure mission capabilities remain effective throughout their lifecycle.

What You'll Do

Requirements Engineering & Technical Baseline

• Analyze user requirements, CONOPS, and high-level system architectures to develop system requirements specifications.

• Guide stakeholders in formulating requirements, evaluating alternative approaches, and assessing technical feasibility.

• Manage system and derived requirements to support delivery of production systems compatible with defined architectures, including DoDAF and SOA environments.

• Develop and allocate system and functional requirements across hardware, software, facilities, and personnel components.

• Derive lower-level requirements and ensure they are complete, correct, unique, unambiguous, realizable, and verifiable.

• Identify functions implied by stakeholder needs and system requirements that are essential to system effectiveness.

• Establish formal requirements-change processes that assess impacts before commitment, maintain traceability, gain stakeholder agreement, eliminate ambiguity, and track open actions through resolution.

• Manage and maintain the technical integrity of the system baseline throughout development, deployment, operations, and maintenance.

• Develop derived Information Assurance requirements addressing confidentiality, integrity, non-repudiation, availability, identification, authentication, access control, accountability, and applicable security mechanisms.

Architecture, Design & System Analysis

• Lead system design and development activities based on system requirements and mission needs.

• Generate alternative system concepts, physical architectures, and design solutions.

• Develop system design solutions that satisfy system requirements and functional analyses.

• Develop comprehensive Service-Oriented Architecture (SOA) solutions.

• Develop operational, technical standards, and systems/services architecture views using applicable DoDAF standards.

• Allocate real-time process budgets and error budgets to system and subsystem components.

• Prepare timeline-analysis diagrams illustrating time-dependent system functions.

• Develop operational scenarios and threads describing interactions among the system, user, and environment across operational, support, maintenance, and disposal needs.

• Develop system-design alternatives considering lifecycle cost, reuse, complexity, risk, system expansion, and growth.

• Use validated models, simulations, and prototypes to mitigate risk and reduce system-development cost.

• Incorporate new plans, designs, and systems into ongoing operations.

Interfaces, Integration & Configuration

• Define and manage interfaces throughout the system lifecycle.

• Fully define software interfaces in terms of origination, destination, stimulus, and data characteristics and hardware interfaces in terms of applicable electrical and mechanical characteristics.

• Capture interface designs using common interface-control formats and maintain interface information in accessible repositories.

• Establish formal procedures for coordinating system-integration activities across multiple teams and ensuring complete interface coverage.

• Improve integration strategies based on the rationale and results of previous engineering decisions.

• Ensure effective periodic review and control of evolving hardware, software, and associated system documentation.

• Establish and support approval of system/component definitions—including requirements, designs, interfaces, and test procedures—to provide a common technical reference for developers.

• Coordinate resolution of cross-discipline action items from CCB meetings, design reviews, program reviews, and test reviews.

• Serve as a member of the Configuration Control Board.

• Participate in Integrated Product Teams developing new capabilities based on development and operational considerations.

Verification, Test & Certification

• Define methods, processes, and evaluation criteria for verifying systems, subsystems, and work products against established requirements.

• Plan verification activities for new and unproven designs early in the development lifecycle with system stakeholders.

• Guide system-development and implementation planning through Systems Engineering Management Plans and system integration and test plans.

• Support planning and test analysis for DoD Certification and Accreditation and other applicable Government C&A processes.

• Maintain alignment among requirements, architecture, design, integration, verification, and test activities.

Risk, Trade Studies & Lifecycle Engineering

• Assess program risks and quantify probability of occurrence and consequences of failure in accordance with approved risk-management plans.

• Develop alternative courses of action, workarounds, and fallback positions with recommended responses for identified risks.

• Monitor and reevaluate risks at appropriate milestones, including use of Earned Value Management data.

• Conduct and/or approve end-to-end system trade analyses to optimize lifecycle operations and appropriately balance non-functional performance characteristics.

• Conduct quantitative analysis in areas such as reliability, maintainability, vulnerability, survivability, producibility, and other non-functional performance considerations.

• Participate in Analysis of Alternatives efforts and recommend preferred solutions based on applicable selection criteria, assumptions, technology limitations, environmental impacts, and lifecycle costs.

• Apply modeling, simulation, prototyping, and engineering analysis to inform technical decisions and reduce development risk.

Standards, Documentation & Acquisition Support

• Maintain knowledge of applicable agency, national, and international system-development standards and apply and enforce appropriate standards to support consistency and hardware/software interoperability.

• Develop and contribute to Systems Engineering Plans, Initial Capabilities Documents, Requirements Specifications, Interface Control Documents, and other technical documentation.

• Review and/or approve systems-engineering documentation to ensure processes and specifications are accurate, comprehensive, complete, and responsive to system needs.

• Support development and review of JCIDS documentation, including Initial Capability Documents, Capabilities Description Documents, and Information Assurance strategies.

• Review and provide input to program and contract Work Breakdown Structures, work packages, and the Integrated Master Plan.

Principal-Level Technical Direction

• Plan and lead Systems Engineering efforts supporting complex mission systems.

• Provide technical leadership for integration of requirements, design, and technology.

• Provide technical direction for the development, engineering, interfacing, integration, and testing of all components of complex hardware/software systems.

• Guide requirements elicitation, analysis and functional allocation, systems requirements reviews, CONOPS and interface-standard development, architecture development, technical and non-technical assessments, and end-to-end flow analysis.

• Maintain responsibility for the technical integrity of assigned Systems Engineering work and associated deliverables.

• Interact with Government stakeholders regarding technical considerations, problems, issues, and conflicts.

• Communicate with program personnel, Government overseers, engineering teams, and senior executives.

This posting is for multiple opportunities.

Required Qualifications

Clearance

• TS/SCI with Polygraph at the time of Application, to be considered for this position.

Education & Experience

• Minimum of twenty (20) years of experience as a Systems Engineer supporting programs and contracts of similar scope, type, and complexity.

• Demonstrated experience planning and leading Systems Engineering efforts.

• Bachelor's degree in Systems Engineering, Computer Science, Information Systems, Engineering Science, Engineering Management, or a related discipline from an accredited college or university.

• Five (5) additional years of Systems Engineering experience may be substituted for the bachelor's degree.

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:

August 28, 2026

Pay Range:

Pay Range $154,050.00 - $278,475.00

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.