Full Stack Software Engineer (TS/SCI)

Full Stack Software Engineer

Pentagon or Reston VA

Clearance: Active TS/SCI Required

About the Role

Marathon TS is seeking an experienced Full Stack Software Engineer to support a high-impact Department of Defense (DoD) AI transformation initiative. This role will work alongside engineers, architects, data scientists, analysts, and mission users to develop innovative technology solutions that support critical mission requirements.

The Full Stack Software Engineer will design, develop, integrate, and deploy secure and scalable applications incorporating agentic AI, large language models (LLMs), knowledge graphs, and modern enterprise software within DoD environments.

The ideal candidate will have a strong full stack development background and an interest in applying AI technologies to solve complex mission and operational challenges.

Key Responsibilities

• Design and implement autonomous AI agents capable of planning, reasoning, and executing multi-step workflows.
• Develop orchestration pipelines using modern agent frameworks.
• Integrate Large Language Models (government-approved) into enterprise applications.
• Develop architectures and/or ingestion pipelines that will use structured and unstructured data.
• Optimize AI workflows for security, performance, explainability, and reliability.
• Develop APIs supporting AI-enabled applications.
• Support the integration of the knowledge graph database and enterprise analytics tools, AI reasoning chains, and mission data.
• Develop scalable microservices and containerized applications.
• Integrate entity resolution tooling into the platform.
• Support the design, configuration, and maintenance of knowledge graphs representing mission data.
• Develop semantic search and context-aware information retrieval solutions.
• Participate in CI/CD pipeline development and automated testing.
• Implement secure coding practices consistent with DoD cybersecurity requirements.
• Perform vulnerability remediation and support Authority to Operate (ATO) activities.

Experience/Clearance

• Active Top Secret clearance with SCI eligibility (TS/SCI required).
• Bachelor's degree in Engineering, Computer Science, Information Systems, Artificial Intelligence, Data Science, or related technical discipline.
• 5+ experience as a full stack developer with upward trajectory. Experience supporting government or defense programs preferred.
• Experience delivering enterprise software to government production environments, including hands on AI/ML initiatives, and complex systems integration efforts.
• Experience on Agile, cross-functional engineering teams delivering modern cloud-based solutions.
• Understanding of secure software development practices, RMF (Risk Management Framework,) relevant NIST publications.
• Strong analytical, debugging, and systems thinking skills with the ability to communicate complex technical concepts to technical and non-technical stakeholders.
• Experience translating mission requirements into AI-enabled software solutions.
• Passion for emerging AI technologies and continuous learning.
• Ability to work independently and collaboratively in multidisciplinary teams.
• Commitment to delivering secure, reliable, and mission-focused software solutions.