Software Engineer Contract Jobs in O Fallon, IL (NOW HIRING)

Description

Are you ready to build software that makes a real-world impact? Leidos is seeking a talented Mid-Level Full Stack Software Engineer to join the Chinook Program supporting an Intelligence Community customer. In this role, you’ll design, develop, and deliver modern software solutions that enable critical national security missions while working alongside some of the industry’s brightest engineers, architects, and mission experts.

As a Full Stack Engineer, you’ll contribute across the entire software development lifecycle, from crafting intuitive user interfaces to building scalable backend services and integrating secure, cloud-native solutions. Working within a collaborative Agile environment, you’ll help deliver high-quality capabilities through iterative development, continuous integration, and DevSecOps best practices.

In this role, you will work on cross-functional development teams to build and maintain microservices, APIs, and web-based applications that support GEOINT data access, visualization, and dissemination. You will contribute to the full software lifecycle and will have the opportunity to work directly with users, cloud engineers, and mission stakeholders.

If you’re passionate about solving complex technical challenges, learning emerging technologies, and developing software that directly supports mission success, this is an exciting opportunity to grow your career while making a meaningful difference.

Position may be performed in the following locations below.  Please note Gaithersburg, MD is the program’s primary work location.

• 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:

• Design, develop, test, and deploy software solutions that support our customer’s GEOINT mission.

• Participate in agile development sprints and contribute to daily stand-ups, sprint planning, and retrospectives.

• Build and maintain secure, containerized applications using technologies such as Docker, Kubernetes, and AWS.

• Develop RESTful APIs and user-facing interfaces with modern tools (e.g., React, Node.js, Flask or Sprint Boot).

• Collaborate with mission users and product managers to refine requirements and improve user experience.

• Support DevSecOps pipelines and ensure code meets security and accreditation standards.

• Participate in code reviews and mentor junior developers as needed.

• Resolve various tasks as prioritized by the team product owner.

Basic Qualifications:

• US citizenship is required per contract.

• Bachelor's degree in Computer Science, Software Engineering, or related field and 4-8 years of prior relevant experience or Master’s with 2-6 years of prior relevant experience.

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

• Proficiency with the following technologies:

  • Web: HTML, CSS, JSON, Ajax, and REST APIs

  • Object-oriented Programming: Python, Java, or 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: AWS, Azure, or similar cloud platforms

  • Relational Database: MySQL, PostgreSQL, or SQL Server

  • Operating System: Windows, Linux

  • Version Control System: Git

• Deep understanding of modern software design patterns and coding standards.

• Experience architecting, developing, and delivering complex software systems into production.

• Experience with CI/CD tools (GitLab CI, Jenkins) and agile collaboration tools (JIRA, Confluence).

• Familiarity with cloud environments such as AWS (C2S or GovCloud) and containerization technologies (Docker, Kubernetes)

• Understanding of secure coding practices and government system accreditation processes (e.g., RMF, STIGs)

• Strong, self-motivated desire to learn new programming languages, tools, frameworks, and techniques.

Preferred Qualifications:

• Frontend Web Development: UI/UX

• NoSQL Database: OpenSearch/Elasticsearch.

• Cloud Exposure:

  • Multi-cloud architectures: AWS, IBM, Google, Azure, and Oracle.

  • Specific AWS Services: S3, SQS, SNS, EC2, CloudFormation and RDS.

• Experience working on a customer contract or in the Intelligence Community (IC).

• Familiarity with geospatial tools and standards:

  • GeoServer

  • PostGIS

  • OGC APIs

  • ESRI ArcGIS

• Exposure to Infrastructure-as-Code (Terraform, Ansible)

• Certifications such as AWS Certified Developer, Security+, SAFe Practitioner or similar.

#Chinook

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.