Software Engineer - TS/SCI with Polygraph

Public Trust: None

Requisition Type: Regular

Your Impact

Own your opportunity to serve as a critical component of our nation’s safety and security. Make an impact by using your expertise to protect our country from threats.

Job Description

Transform technology into opportunity as a Software Engineer (SME) with GDIT. We are seeking a hands-on software engineer with expertise in designing, developing, and sustaining cloud‑enabled applications in Lean Agile environments to deliver secure, scalable, and maintainable mission‑critical customer systems. The role requires expertise in frontend and backend Web development and modern search engineering technologies, including Large Language Models (LLM), Retrieval‑Augmented Generation (RAG), and AI‑assisted retrieval system capabilities development.

KEY TASKS:

• Participate in all Lean Agile scrums, sprint planning, and grooming sessions.
• Consult and coordinate with stakeholders for problem resolution, task scheduling, resource needs, and task clarification.
• Work in partnership with an integrated team of staff and contractors.
• Coordinate and collaborate with security, operations, engineering, testing, and other teams to provide system information and technical support.
• Understand and work within approved cloud environments (e.g., AWS).
• Design, develop, and modify software systems.
• Unit test software and perform code reviews.
• Design and implement scalable search and retrieval systems leveraging Elasticsearch.
• Develop and integrate LLM‑powered capabilities, including Retrieval‑Augmented Generation (RAG) pipelines.
• Document and track vendor software roadmaps for software and patch version updates.

REQUIRED SKILLS AND DEMONSTRATED EXPERIENCE:

• Demonstrated experience working in Lean Agile Development environment.
• Demonstrated experience translating customer and system requirements into actionable design specifications.
• Demonstrated experience designing system interfaces, including defining integration points, data flows, and data exchange workflows.
• Demonstrated experience building or integrating LLM-based solutions, including RAG pipelines, semantic search, and AI-assisted retrieval systems.
• Demonstrated experience designing and implementing data pipelines for hybrid search (BM25 + vector search) in RAG workflows, covering ingestion, chunking, embeddings, and vector retrieval.
• Demonstrated experience with Elasticsearch, included index design and optimization, query development, relevance tuning, and cluster scaling.
• Demonstrated hands-on experience in frontend Single Page Applications (SPA) development using React (hooks), HTML5, CSS3, and modern JavaScript best practices.
• Demonstrated hands-on experience in backend development, including designing and building RESTful APIs with Node.js and Express.js (or comparable modern backend frameworks).
• Demonstrated hands-on experience troubleshooting web protocols and server technologies, including Apache Tomcat, Node.js, Web Services, and SSL/TLS security configurations.
• Demonstrated experience using modern testing platforms such as Jest or Karma.
• Demonstrated experience with DevOps tools including Git, Jenkins, and Nexus.

HIGHLY DESIRED SKILLS AND DEMONSTRATED EXPERIENCE:

• Experience with the customer’s Lean Agile methodology.
• Experience evaluating, selecting, or integrating LLMs (e.g., OpenAI, open‑source models) into enterprise applications.
• Experience with vector databases, hybrid search (keyword + semantic), and relevance optimization.
• Experience with or exposure to RAG, LLM integrations, or semantic search.
• Experience with Elasticsearch or similar search platforms, with some exposure to optimization or scaling.
• Experience mentoring teams in search engineering and AI/LLM best practices, with a demonstrated ability to improve overall team capability.
• Experience with React + Node/Express development, with the ability to quickly ramp into search/AI domains.
• Experience working on APIs or systems that integrate with external AI/ML services.
• Demonstrated ability to learn quickly with guidance and become a team multiplier.

WHAT YOU’LL NEED TO SUCCEED:

• Education: Bachelor’s degree in Computer Science, Engineering, or a related technical discipline, or the equivalent combination of education, technical certifications or training, or work experience.
• Experience: 10+ years
• Security clearance: TS/SCI with Polygraph
• Location: Chantilly, VA (On Customer Site)
• US Citizenship Required

#WeAreGDIT
#JET
#GDITEnhanced2026
#VA_2026Alumni

Work Requirements

Years of Experience

10 + years of related experience

* may vary based on technical training, certification(s), or degree

Certification

Travel Required

Less than 10%

Citizenship

U.S. Citizenship Required