Software Engineer - TS/SCI with Polygraph

Company: GD Information Technology
Location: Chantilly
Posted on: April 2, 2026

Job Description:

Type of Requisition: Regular Clearance Level Must Currently Possess: Top Secret SCI Polygraph Clearance Level Must Be Able to Obtain: Top Secret SCI Polygraph Public Trust/Other Required: None Job Family: Software Engineering Job Qualifications: Skills: Agile Methodology, Large Language Model (LLM) Fine-Tuning, Microsoft Azure Certifications: None Experience: 10 years of related experience US Citizenship Required: Yes Job Description: Transform technology into opportunity as a Software Engineer with GDIT. A career in enterprise IT means connecting and enhancing the systems that matter most while you build valuable skills that will help you in your career. At GDIT you’ll be at the forefront of innovation and play a meaningful part in improving how agencies operate. KEY TASKS: Participate in all Lean Agile scrums, sprints and grooming sessions. Consult and coordinate appropriately for problem resolution, task scheduling, new resource requirements, and task clarification. Work in partnership with an integrated team of staff and contractors. Understand the cloud environments, such as AWS or Azure. Coordinate and collaborate with security, operations, engineering, testing and other teams to provide system information and technical support. Design, develop and modify software systems. Document and track vendor software roadmaps for software and patch version updates. Unit test their software and perform code. Design and implement scalable search and retrieval systems leveraging Elasticsearch. Develop and integrate LLM-powered capabilities, including Retrieval-Augmented Generation (RAG) pipelines REQUIRED SKILLS AND DEMONSTRATED EXPERIENCE: Demonstrated experience working in Lean Agile Development environment. Demonstrated experience building or integrating LLM-based solutions, including RAG, semantic search, or AI-assisted retrieval systems. Demonstrated experience developing detailed design and associated deliverables. Demonstrated experience translating customer and system requirements into design. Demonstrated experience designing system interfaces. Demonstrated experience developing Single Page Applications using React (modern hooks-based architecture), HTML5, and CSS3. Demonstrated hands-on experience developing RESTful APIs using Node.js and Express (or comparable modern backend frameworks).Demonstrated hands-on experience with and troubleshooting of Internet and Web related protocols and technologies such as Tomcat, Nodejs, Web Services, or SSL. Demonstrated experience with testing platforms such as Jest or Karma. Demonstrated hands-on experience working with DevOps tools such as Git, Jenkins, or Nexus Demonstrated hands-on experience with Elasticsearch (index design, querying, relevance tuning, and scaling). Demonstrated experience designing or implementing data pipelines to support search and/or RAG workflows (e.g., ingestion, chunking, embeddings, vector search). HIGHLY DESIRED SKILLS AND DEMONSTRATED EXPERIENCE: Demonstrated recent experience with the Sponsor’s Lean Agile methodology Experience evaluating, selecting, and integrating LLMs (e.g., OpenAI, open-source models) into enterprise applications. Experience with vector databases, hybrid search (keyword semantic), and relevance optimization. Ability to lead or mentor teams in adopting search AI/LLM best practices (strong preference for candidates who can elevate team capability, not just contribute individually). 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 GDIT IS YOUR PLACE: 401K with company match Comprehensive health and wellness packages Internal mobility team dedicated to helping you own your career Professional growth opportunities including paid education and certifications Cutting-edge technology you can learn from Rest and recharge with paid vacation and holidays WeAreGDIT JET GDITEnhanced2026 VA_2026Alumni The likely salary range for this position is $158,855 - $214,921. This is not, however, a guarantee of compensation or salary. Rather, salary will be set based on experience, geographic location and possibly contractual requirements and could fall outside of this range. Scheduled Weekly Hours: 40 Travel Required: Less than 10% T elecommuting Options: Onsite Work Location: USA VA Chantilly Additional Work Locations: Total Rewards at GDIT: Our benefits package for all US-based employees includes a variety of medical plan options, some with Health Savings Accounts, dental plan options, a vision plan, and a 401(k) plan offering the ability to contribute both pre and post-tax dollars up to the IRS annual limits and receive a company match. To encourage work/life balance, GDIT offers employees full flex work weeks where possible and a variety of paid time off plans, including vacation, sick and personal time, holidays, paid parental, military, bereavement and jury duty leave. To ensure our employees are able to protect their income, other offerings such as short and long-term disability benefits, life, accidental death and dismemberment, personal accident, critical illness and business travel and accident insurance are provided or available. We regularly review our Total Rewards package to ensure our offerings are competitive and reflect what our employees have told us they value most. We are GDIT. A global technology and professional services company that delivers consulting, technology and mission services to every major agency across the U.S. government, defense and intelligence community. Our 30,000 experts extract the power of technology to create immediate value and deliver solutions at the edge of innovation. We operate across 50 countries worldwide, offering leading capabilities in digital modernization, AI/ML, Cloud, Cyber and application development. Together with our clients, we strive to create a safer, smarter world by harnessing the power of deep expertise and advanced technology. Join our Talent Community to stay up to date on our career opportunities and events at gdit.com/tc . Equal Opportunity Employer / Individuals with Disabilities / Protected Veterans

Keywords: GD Information Technology, Tuckahoe , Software Engineer - TS/SCI with Polygraph, IT / Software / Systems , Chantilly, Virginia