Principal Software Developer

Naval Nuclear Laboratory
parental leave, tuition assistance, 401(k)

Apr 10, 2026
About Us Working at the Naval Nuclear Laboratory we foster pride in belonging to an organization whose culture is made up of these core values: Trust, Empowerment, and Collaboration. Our company promotes a positive culture while ensuring the safety and reliability of our nation's naval nuclear reactors, and training the Sailors who operate those reactors in the U.S. Navy's submarines and aircraft carrier Fleets. Looking for a lifetime career? Apply today! Job Description The Core Analysis Process System (CAPS) Project is looking to hire a principal software engineer to lead the reactor engineering community in developing and implementing complex software solutions for scientific and engineering problems. The CAPS Project works directly with our engineers to provide common software engineering solutions for the reactor design community, applicable to all naval nuclear core designs. The project is focused on the ability to provide robust, user friendly, automated tools to evaluate thermal hydraulic and reactor performance design conditions. As a Principal Software Developer on the CAPS Project, the qualifying individual will need to be able to directly mentor and oversee multiple software engineers and nuclear engineers in designing, developing, testing, verifying, and maintaining engineering applications and programs using modern computing architectures. Additionally, the selected individual will work closely with management and leads to define the future of the scientific and engineering work efforts across the reactor engineering, data science and high performance computing technologies with a focus on near term execution. Particular application areas include nuclear reactor physics, reactor thermal performance and casualty analysis, and data science. Required Combination of Knowledge and Skill Bachelors degree from an accredited college or university in a related technical, engineering or science field and a minimum of 9 years of relevant experience; or Masters degree from an accredited college or university in a related technical, engineering or science field and a minimum of 7 years of relevant experience; or Doctorate degree from an accredited college or university in a related technical, engineering, science field and a minimum of 3 years of relevant experience; or Currently a Principal Reactor Training Engineer, Refueling Engineer, or Field (RPCO) Engineer at the Company. Preferred Skills Strong programming skills withcompiled (e.g., Java, C, C++ or Fortran) and/or interpreted (e.g., Python) scientific computing languages Demonstrated experience with all aspects of software architecture (design, implementation, testing, maintenance, configuration management) Experience with client-server software systems used across multiple operating environments (e.g. Windows, Linux) Experience with Graphical User InterfaceParallel programming and running parallel jobs on supercomputing systems Experience functioning within an agile development methodology Ability to work effectively across multiple projects simultaneouslyDemonstrated ability and passion for developing scientific software Capacity to work independently, as well as within interdisciplinary teams with minimal supervision Compensation and Benefits Health, Dental, Vision & Voluntary Benefits Disability, Life & Accident Insurance 401(k) Savings program & Capital Accumulation Plan Personal & Medical Time Off Paid Parental Leave Flexible Work Schedules Tuition Assistance for Eligible Employees Student Debt Benefit Personal Time Off Sell Program Employee Assistance Program (EAP) Wellness Program Visit us online to view all NNL benefits! Pay Range $117,900.00 - $184,300.00 annually Salary information provided is a general guideline only. Annual salary is based upon candidate experience and qualifications, as well as market and business considerations. The Naval Nuclear Laboratory is operated for the U.S. Department of Energy (DOE) by Fluor Marine Propulsion, LLC (FMP), a wholly owned subsidiary of Fluor Corporation. Naval Nuclear Laboratory personnel are FMP employees who work at four DOE facilities: Bettis Atomic Power Laboratory, Knolls Atomic Power Laboratory, Kenneth A. Kesselring Site, and Naval Reactors Facility, and at the U.S. Department of Defense-owned Nuclear Power Training Unit-Charleston. FMP employees also have an established presence at numerous shipyards and vendor locations. For nearly 70 years, the Naval Nuclear Laboratory has developed advanced nuclear propulsion technology, provided technical support, and trained world-class nuclear operators to ensure the safe and reliable operation of our nation's submarine and aircraft carrier Fleets. The Naval Nuclear Laboratory is a national asset solely dedicated to the Naval Nuclear Propulsion Program. We rely on the dedication and innovation of our nearly 8000 engineers, scientists, technicians, and support personnel. All candidates must be U.S. citizens. Applicants selected will be subject to a Federal background investigation and must meet eligibility requirements for access to classified matter. FMP is a government contractor and maintains a drug free workplace and workforce. All candidates must be able to pass a drug test in compliance with FMP company policy and 10 CFR 707. Marijuana is a Federal Schedule I controlled substance and illegal under Federal Law. Therefore, FMP is required to test for marijuana. Fluor Marine Propulsion, LLC is an Equal Opportunity Employer, including disability/vets. All qualified applicants will receive consideration for employment without regard to race, color, age, sex, religion, national origin, disability, veteran status, genetic information, or any other criteria protected by federal, state, or local law. Apply Now