Leidos is seeking a Lead Software Developer - Early Systems Integration (ESI) to be based in Gaithersburg, MD; Eagan, MN; or Egg Harbor, NJ. This position will support the United Kingdom National Airspace System Replacement Product Delivery Team - UK NASR PDT. This effort delivers enhanced capabilities to replace and modernize the current operational system supporting UK air traffic services.
You will join a dynamic engineering team responsible for building and sustaining real-time, high-availability, safety-critical systems that directly support national airspace operations.
Location
This is a U.S.-based position that offers a balanced 50% hybrid schedule between 2-3 days in the office per week.
What You’ll Do
Design, develop, execute integration and test plans, procedures, and cases to verify system functionality, and performance, and maintain software for real-time, high-availability systems
Participate in agile software development activities as part of a collaborative engineering team
Analyze complex system requirements and translate them into efficient, maintainable software test plans and cases.
Lead and mentor junior integrators, influencing technical direction and promote best practices in integration and verification
Participate in Agile ceremonies including daily stand-ups, release planning, and sprint reviews as need in support of the SW teams and the build teams.
Collaborate with software engineers, system engineers, and program leadership to ensure testability of system design and alignment with project schedules
Promote cross-program collaboration, and sustainable development practices
Support system integration activities, including hardware and low-level communications interfaces
Required Qualifications
Bachelor’s degree in Computer Science or related field with 4–8 years of relevant experience. Additional relevant experience may be use in lieu of degree.
OR Master’s degree with 2–6 years of relevant experience
Strong object-oriented programming experience
Proficiency in Perl, Python and shell scripting
Experience developing real-time, multi-threaded, high-availability systems
Experience leading integration and test activities for complex software systems
Strong hands-on integration experience with large, distributed, or real-time systems
Experience with Linux environments (Red Hat), virtual machines, and hypervisors
Experience with low-level communications protocols (TCP/IP, UDP, SCTP)
Experience with hardware or complex system integration
Familiarity with system maintenance and lifecycle concepts
Experience with source control and configuration management tools
Ability to plan and prioritize work effectively in a fast-paced environment
Strong verbal and written communication skills
Demonstrated ability to work independently and collaboratively
US Citizenship Required
Ability to obtain and maintain a Public Trust clearance
Successful completion of background investigations as required by the government customer
Preferred Qualifications
Experience with test automation frameworks
Familiarity with AI/ML tools applied within software development workflows
Familiarity with Agile life cycle
Advanced integration experience in one or more of the following areas:
New system functionality integration
Regression testing
Problem determination and root cause analysis
Data reduction and analysis
Problem verification and change validation
Air Traffic domain knowledge or experience supporting air traffic programs
Experience operating in fast-paced, high-accountability environments requiring independent execution
Why Leidos
You’ll contribute to software systems where reliability, performance, and precision are essential. This is an opportunity to work on mission-critical infrastructure supporting national airspace operations — collaborating with experienced engineers to modernize complex, real-world systems.
If you are motivated by solving technically challenging problems in regulated, operational environments, we encourage you to apply.
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.
August 21, 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 $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 is a Fortune 500® innovation company rapidly addressing the world’s most vexing challenges in national security and health. The company's global workforce of 48,000 collaborates to create smarter technology solutions for customers in heavily regulated industries. Headquartered in Reston, Virginia, Leidos reported annual revenues of approximately $15.4 billion for the fiscal year ended December 29, 2023.
Leidos was cited for the meaningful work employees perform that is challenging, impactful, and aligned with our customers’ missions as reasons professionals want to work and stay at our company. Leidos has also been named to lists including Forbes’ Best Employers for Diversity, Forbes’ America’s Best Employers for Women, Military Times Best for Vets Employers, and Ethisphere Institute’s World's Most Ethical Companies®.
Employees enjoy career enrichment opportunities available through mobility and development and experience rewarding relationships with supportive supervisors and talented colleagues and customers. Employees appreciate our flexible work environment, allowing for and encouraging a true work-life balance. Our professionals are also excited about our Employee Resource Groups, like the Collaborative Outreach with Remote and Embedded Employees (CORE), which strives to create an environment where every employee, regardless of location, feels fully engaged as a valued employee of Leidos.
Your most important work is ahead, visit careers.leidos.com for our latest opportunities.