Software Engineer Software Developer Jobs in Saint Peters, MO

Description

Join a Mission That Matters!

Are you a highly skilled Software Engineer ready to tackle complex technical challenges that directly support our nation’s intelligence mission? Leidos is seeking an accomplished Software Engineer Subject Matter Expert (SME) to join the Chinook Program supporting our Intelligence Community customer.

This is an exciting opportunity to bring your software engineering expertise to a high-impact mission where innovation, technical excellence, and teamwork make a real difference. You will work alongside talented engineers, architects, mission experts, and government stakeholders to develop and deliver secure, scalable, and modern software capabilities that support critical national security objectives.

As a Software Engineer SME, you won’t simply be writing code, you’ll help shape technical solutions, influence architecture, solve challenging engineering problems, and elevate the capabilities of the team around you. We are looking for a hands-on technical leader who thrives in a collaborative environment and is excited about applying modern software engineering practices to meaningful mission challenges.

In this role you will provide hands-on technical leadership across the full software development lifecycle, designing, developing, integrating, testing, deploying, and maintaining mission-critical applications and services. The SME will serve as a senior technical authority within the development team, helping establish sound engineering practices, resolve complex technical challenges, mentor other engineers, and collaborate closely with government and contractor stakeholders.

Position may be performed in the following locations below. 

• Gaithersburg, MD
• Alexandria, VA
• Chantilly, VA
• Englewood, CO
• St. Louis, MO
• Tucson, AZ 

Active Top Secret/SCI with the ability to successfully pass a Polygraph examination.

Primary Responsibilities:

• Serve as the senior technical SME and technical advisor for mission applications under the Chinook program.
• Design, develop, integrate, test, deploy, and maintain modern web applications and backend services.
• Develop scalable, maintainable, and secure software across both front-end and back-end tiers.
• Translate mission and technical requirements into robust software architecture and implementation plans.
• Provide technical leadership in software design, architecture, coding standards, code reviews, and engineering best practices.
• Develop and maintain RESTful APIs, microservices, data services, and system integrations.
• Build responsive and user-focused front-end interfaces using modern web development frameworks
• Design and optimize database schemas, queries, data-access layers, and data-processing workflows.
• Troubleshoot complex application, integration, performance, and production issues.
• Support automated testing, continuous integration/continuous delivery (CI/CD), and DevSecOps practices.
• Contribute to containerized and cloud-enabled application environments as applicable to the program.
• Participate in Agile/Scrum ceremonies, sprint planning, backlog refinement, demonstrations, and technical working sessions.
• Mentor junior and mid-level software engineers and promote consistent engineering practices across the team.
• Identify opportunities to improve application performance, reliability, security, scalability, and maintainability.
• Evaluate emerging technologies and recommend solutions based on mission requirements and technical feasibility.

Basic Qualifications:

• US citizenship is required per contract.
• Bachelor's degree in Computer Science, Software Engineering, or related field and 12-15 years of prior relevant experience or Master’s with 10-13 years of prior relevant experience.
• Proficient with the following technologies:
  • Web: HTML, CSS, JSON, and REST APIs
  • Object-oriented Programming: Python, Java, and JavaScript
  • Advanced Programming: Go
  • Front-end and Back-end Frameworks: React, Angular, Vue.js, jQuery, Spring Boot, Django, Node.js, Flask, or Svelte.
  • Cloud Development:
    • Multi-cloud architectures: AWS, IBM, Google, Azure, and Oracle.
    • Specific AWS Services: S3, SQS, SNS, EC2, CloudFormation and RDS
  • Relational Database: MySQL, PostgreSQL, or SQL Server
  • NoSQL Database: OpenSearch/Elasticsearch.
  • Operating System: Windows, Linux
  • Version Control System: Git
• Proficiency with AWS (C2S/GovCloud) and Infrastructure-as-Code (Terraform, CloudFormation).
• Established experience building and deploying containerized services (Docker/Kubernetes).
• Solid understanding of DevSecOps tools: GitLab CI/CD, Jenkins, SonarQube, Nexus, Keycloak, Vault.
• In depth knowledge of Agile/Scrum practices and tools (JIRA, Confluence)
• Solid understanding of customer specific data types and standards, such as OGC WMS/WFS, NSG, and GEOINT workflows.

Preferred Qualifications:

• Frontend Web Development: UI/UX
• Prior experience supporting Intelligence Community mission systems.
• Experience with messaging/event-driven architecture.
• Experience with observability, logging, monitoring, and application performance management.
• Advanced certifications such as AWS Certified Developer or Solutions Architect, CISSP, SAFe Agile or similar.

#Chinook

#NSBA

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.

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 LeidosCareersFraud@leidos.com.

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.