Full Stack System Engineer Developer Jobs in Saint Louis, MO

The Leidos National Solutions Division has an exciting opportunity for a Journeyman Full Stack Engineer to assist with the software development, maintenance, integration, deployment, and sustainment of maritime systems.

• This role is responsible for adaptive, corrective, preventive and perfective maintenance of maritime systems software.
• This role uses best practices and patterns to perform design, development, and automated testing of software modules via DevSecOps in an Agile team.
• This role involves software system development, including the design, development, troubleshooting, and debugging of software programs for software enhancements and maintenance.
• Participate in peer reviews and unit testing and must be adaptable to different responsibilities.
• Duties include software requirements analysis and development of software products in a maintenance setting.
• This role is responsible for identifying software and hardware dependencies and capacities.
• Creating and maintaining documentation is part of this role.

• Requires a BS in Information Systems, Information Technology, Computer Science or closely related discipline and 4+ years of prior relevant experience or master’s with 2+ years of prior relevant experience; OR 4 years of experience in lieu of degree
• Proficient in software development projects or software integration projects in a service-oriented environment (Cloud, SOA, Web-Services) or virtualization environment
• Proficient in AWS/Cloud technologies
• Experience with cloud-based architecture
• Understanding of DevOps methodologies and workflow
• Knowledge of the Architectural, SW Development and SW Sustainment Practices
• Familiar with Vue, NodeJS, PostgreSQL
• Familiar with Git/GitLab or other source code control tools
• Familiar with Amazon Web Services (S3 Buckets, EC2, Reserved Instances, etc.)
• Familiar with System Engineering documentation creation (VDDs, diagrams, etc.)
• Familiar with team collaboration tools (Jira, Confluence, RocketChat)
• Must possess an active Top Secret Security Clearance with ability to obtain SCI and a polygraph post hire

• DOD 8570 Certification (Security+ or equivalent or higher)
• Understanding of Containers (Docker, ECS, EKS, Fargate, AKS)

Pay Range $69,550.00 - $125,725.00 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.

Original Posting: August 14, 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.

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 $17.2 billion for the fiscal year ended January 2, 2026. For more information, visit www.Leidos.com.

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 here.

Leidos will never ask you to provide payment-related information at any part of the employment application process. And Leidos will communicate with you only through emails that are sent from a Leidos.com email address. If you receive an email purporting to be from Leidos that asks for payment-related information or any other personal information, please report the email to spam.leidos@leidos.com.

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.