Senior Software Developer (TS/SCI)

Marathon TS is seeking an experienced and collaborative Senior Software Developer to join our team and support one of our intelligence customers in Springfield, VA. The ideal candidate is a self-starter with strong AI development experience who thrives in a mission-focused environment and enjoys solving complex technical challenges.

This position requires an active TS/SCI security clearance and offers the opportunity to work on innovative AI solutions supporting critical intelligence missions. The successful candidate will bring strong technical expertise, a collaborative mindset, and the ability to deliver high-quality solutions in a secure government environment.

Job Summary:

Designs, develops, evaluates, plans and tests AI features across a few software programs and applications

Job Duties:

• Integrate multiple data streams into customer system
• Complete Cloud platform migrations (between currently existing and available platforms)
• Develop AI features for existing Ontology-based software applications
• Creates sustainable software applications – work is estimated accurately, branching strategies are efficient, code repos are maintained, etc.
• Works as a member of an agile scrum team and participates in regular agile ceremonies applying scrum methodologies – daily stand up, planning, sprint reviews, demos, retrospectives.
• Implements requirements from the product backlog
• Assists in writing backlog requirements/user stories
• Utilizes a modern DevSecOps approach in building software applications
• Develop and modify applications, software, services, utilities, interfaces, and IT systems that support systems and analysts.

Required Skills/Qualifications:

• 8 years of experience
• Bachelor's Degree in computer science, computer engineering, systems engineering or any related field/major, or 6 additional years of experience in information technology.
• Senior-level software development experience designing, developing, and maintaining secure, scalable, and mission-focused applications.
• Strong programming experience with Python, Java, and Scala.
• Experience developing and integrating RESTful APIs, Git-based workflows, automated unit/integration/system testing, CI/CD pipelines, and modern software delivery practices.
• Hands-on experience with Docker/containerization, microservice architectures, Helm, and development container environments.
• Experience developing applications using Generative AI technologies, including Retrieval-Augmented Generation (RAG), Large Language Models (LLMs), and LLM-enabled workflows.
• Experience designing, deploying, and supporting cloud-native applications using AWS, OpenShift, and Kubernetes.
• Experience integrating, transforming, and managing data from multiple sources, organizations, and network environments.
• Experience deploying applications into new or complex network environments.
• Experience applying DevSecOps practices, including secure software development, code hardening, dependency/package updates, vulnerability remediation, and automated security scanning.
• Ability to troubleshoot complex software systems and collaborate across development, infrastructure, security, and mission teams.

Desired Skills/Qualifications:

• Familiarity with data normalization, transformation, and visualization techniques.
• Familiarity with graph-based data models, data relationships, and advanced data structures.
• Experience working in Agile/Scrum development environments.
• Experience developing and presenting technical metrics, status reports, and project updates to internal leadership and external customers.
• Demonstrated ability and willingness to mentor junior developers and contribute to team engineering practices.

Location: Company Site

US Citizenship Required

TS/SCI Required