Principal Software Engineer

Description

Leidos Defense Systems is seeking a talented Principal Software Engineer that contributes to and mentors software teams to create unique solutions for complex problems. We have offices across the United States engaging in the defense, space, cyber and commercial fields. We provide responsive, cost-effective engineering, scientific and IT solutions.

This role is part of an engineering matrix organization with the Program Integration team that supports many programs that span business areas. Responsibilities include contributing to and mentoring software development teams during the software development process to support a variety of customers, often with competing requirements.

The candidate must be comfortable in a fast-paced working environment and be a motivated independent learner. The candidate must be highly organized and possess strong verbal and written communication skills.

• Candidate must possess a Bachelor's Degree in Computer Science, Computer Engineering, or equivalent degree from an ABET-accredited university.
• Candidate must have at least 12+ years of experience or 10+ years with a Master's.
• Candidate must have experience in analyzing and developing requirements, designing and maintaining software products, and implementing software designs. Candidate must be able to parse ambiguous requirements and translate into team direction and guidance.
• Candidate must have experience in desktop software development activities. Candidate must have experience in software development, data structures, object oriented design, and effective unit test. Candidate must have experience with multiple languages that include C or C++, C# or Java, and Python or other similar scripting language.
• Candidate must have experience with Agile/Scrum methodologies and task management.
• Candidate must have experience mentoring teammates and providing guidance to accomplish tasks and projects.
• Candidate must have experience with software best practices such as peer reviews, automated testing, and document generation.
• Candidate must be a resident of the North Alabama area or willing to relocate to the Huntsville - North Alabama, AL area.

• Master's Degree in Computer Science, Computer Engineering, or equivalent degree from an ABET-accredited university would be considered a plus.
• Prior Unity Real-Time Development platform experience and working with modeling and simulation platforms is a plus.
• Prior experience interviewing or contributing to proposals is a plus.

At Leidos, we don't want someone who "fits the mold"
-we want someone who melts it down and builds something better. This is a role for the restless, the over-caffeinated, the ones who ask, "what's next?" before the dust settles on "what's now."

If you're already scheming step 20 while everyone else is still debating step 2... good. You'll fit right in.

January 9, 2026

Pay Range $ - $

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 at

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 $16.7 billion for the fiscal year ended January 3, 2025. For more information, visit

Beware of fake employment opportunities using Leidos' name. Leidos will never ask you to provide payment-related information during any part of the employment application process (i.e., ask you for money), nor will Leidos ever advance money as part of the hiring process (i.e., send you a check or money order before doing any work). Further, Leidos will only communicate with you through emails that are generated by the  automated system - never from free commercial services (e.g., Gmail, Yahoo, Hotmail) or via Whats App, Telegram, etc.

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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…