Principal Software Engineer (SWE-4) with Security Clearance

R-00186427 Description Leidos has a new and exciting opportunity for a Principal Software Engineer in our Intelligence Sector's Cyber & Analytics Business Area (CABA).  Our talented team is at the forefront in Security Engineering, Computer Network Operations (CNO), Mission Software, Analytical Methods and Modeling, Signals Intelligence (SIGINT), and Cryptographic Key Management. At Leidos, we offer competitive benefits, including Paid Time Off, 11 paid Holidays, 401K with a 6% company match and immediate vesting, Flexible Schedules, Discounted Stock Purchase Plans, Technical Upskilling, Education and Training Support, Parental Paid Leave, and much more.  Join us and make a difference in National Security!   Job Summary: Our LOE program provides our customer's Operations organization with the best possible solutions for their mission needs. We achieve this through rapid prototyping, new development, and advanced technology research. From leading-edge visualizations to analytic development, we're always pushing the boundaries to find new and better data sources and tradecraft to answer intelligence questions. With a focus on collaboration and a fast-paced environment, our prototype development program is the ideal place to grow your skills and make a real impact. Click  here  to learn more about how this program “Delivers Mission Success!” Seeking a motivated Principal Software Engineer to support the exciting Advanced Analytics Team mission. The engineer will work closely with mission stakeholders to analyze software requirements, design innovative technical solutions, develop software applications, and implement high-performance capabilities supporting advanced mission objectives. *Qualified candidates are eligible for enhanced incentives including up to a $25K cash sign on bonus or a paid time off bonus. Job Responsibilities/Qualifications: * Mission Focus: Design, develop, test, debug, and maintain software applications supporting mission requirements. Analyze customer needs, develop software prototypes, engineer technical solutions, implement algorithms, and translate conceptual designs into scalable software architectures.
* Technical Proficiency: Develop and debug software using object-oriented programming languages; perform software engineering and technical design activities; analyze and understand legacy code; develop efficient algorithms utilizing data structures, dynamic programming, heuristics, and modeling techniques; conduct software testing and troubleshooting; work at the operating system level, including file I/O, system interfaces, and low-level programming concepts; and develop advanced tools for binary analysis, shellcode detection, malware analysis, function identification, and reverse engineering of compiled software.
* Qualifications: Bachelor's degree plus eleven (11) years of relevant experience or equivalent. Proficiency with Python, and ability to read/understand C/C++, and Assembly (x86). Experience with software architecture, operating system design, compilers, and debugging. Comfortable working with operating system internals, low-level software development, file I/O, system APIs, memory management, and executable program analysis.
* Security Clearance: Active TS/SCI with Polygraph required to be considered for this role.
* Desirable Skills: Familiarity with malware analysis, reverse engineering, and protocol analysis. At Leidos, the opportunities are boundless. We challenge our staff with interesting assignments that allow them to thrive professionally and personally. For us, helping you grow your career is good business. We look forward to learning more about you – apply today! Careers.leidos.com CONMD 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 30, 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 $131,300.00 - $237,350.00 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. About 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 $16.7 billion for the fiscal year ended January 3, 2025. For more information, visit www.Leidos.com . 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 at www.leidos.com/careers/pay-benefits . Securing Your Data 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 Leidos.com automated system – never from free commercial services (e.g., Gmail, Yahoo, Hotmail) or via WhatsApp, Telegram, etc. If you received an email purporting to be from Leidos that asks for payment-related information or any other personal information (e.g., about you or your previous employer), and you are concerned about its legitimacy, please make us aware immediately by emailing us at . If you believe you are the victim of a scam, contact your local law enforcement and report the incident to the U.S. Federal Trade Commission . Commitment to Non-Discrimination 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.