Software Engineer C#

Leidos is seeking a Software Engineer (C#) to work for the Security Enterprise Solutions(SES) business unit in Vista, CA. The SES business unit at Leidos designs and manufactures highly complex security equipment for use at border crossings, airports, seaports, and other transportation mechanisms. Our products include radiation detectors and spectrometers, X-ray and gamma ray scanners for cars, trucks and trains, and CT explosives detection equipment for airline passenger baggage. The ultimate goal for this position will be to update existing design as well as introduce new products to our already extensive line of security detection products. The products being developed through this effort are truly novel, and will make travel and trade safer, healthier, and more efficient on a global level.

As part of a cross-functional team, the Software Engineer (C#) will develop and maintain cargo inspection detection systems for the Ports and Borders group at Leidos. This role requires a solid foundation in software development, a commitment to learning, and the ability to contribute to innovative solutions.

Key Responsibilities:

Technical Contribution and Collaboration:

• Assist in the design, development, testing, and maintenance of services, simulators, and diagnostics (WPF and Blazor) using C#.
• Collaborate with team members to ensure alignment with best practices and coding standards.
• Contribute to the adoption of tools and processes that enhance productivity and innovation.
• Work closely with senior engineers to gain experience and contribute to technical solutions.

Software Development and Security Compliance:

• Develop software that adheres to industry security standards and contributes to the security compliance of the codebase and coding practices.
• Utilize object-oriented design principles, practices, and patterns to ensure the codebase is reusable and maintainable.
• Apply Agile development practices, including Test-Driven Development (TDD) and Continuous Integration, to ensure high-quality, continuously tested code.
• Collaborate with Electrical Engineering, Mechanical Engineering, and Scientists to meet customer requirements.

Problem Solving and Innovation:

• Troubleshoot and resolve technical issues under the guidance of senior engineers.
• Contribute to innovation by researching and integrating best practices to develop effective solutions.

Communication and Reporting:

• Communicate effectively within a small cross-functional development team environment.
• Report project status and issues to management as required.

Required Skills:

• BS Degree and 2+ years of experience or Masters Degree with less than 2 years of experience. May consider additional experience in lieu of a degree.
• Must have the ability to obtain a Public Trust clearance (US citizenship required).
• Programming with production product development experience in C# required.
• Solid understanding of object-oriented design (OOD) principles and practices.
• Familiarity with Agile development environments, including Test-Driven Development (TDD) and Continuous Integration.
• Ability to create basic design documentation and other technical documentation.
• Strong troubleshooting and bug-fixing skills.
• Effective communication and collaboration skills in cross-functional team environments.
• Must be willing to travel abroad. If travel is necessary, typically it will be < 10%

Desired Skills:

• Familiarity with AI-based software development tools.
• Experience developing software that complies with industry security standards.
• Proficiency with revision control (e.g., Git), multi-threading, TCP/IP networking, bus architectures, Web Services, Blazor, containers (e.g., Docker), Visual Studio, C++, SQL Server, and interfacing with real-time/embedded systems.
• Experience, familiarity, or interest with embedded, RTOS, and/or PLC code.
• Knowledge of image processing techniques.

Check out the links below to learn more about Security Enterprise Solutions (SES)

We’re not looking for perfectly polished resumes or perfect fits. We’re looking for people who break limits, ask hard questions, and don’t wait to be told what’s next. At Leidos, we’re not following the roadmap — we’re redrawing it.

Original Posting:

November 4, 2025

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 $67,600.00 - $122,200.00

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.