Senior Software Engineer - TS/SCI with Polygraph with Security Clearance

At GDIT, people are our differentiator. As a Senior Software Engineer supporting our Intelligence Community customer, you will be trusted to solve complex technical challenges while delivering mission-critical capabilities that directly support national security objectives. We are seeking a highly motivated and experienced software engineer with an active TS/SCI clearance with Polygraph to join an Operations and Maintenance (O&M) team responsible for supporting enterprise applications used across the Intelligence Community.

In this role, you will collaborate with Agile development teams to maintain, enhance, and improve applications serving a broad range of IC customers. Responsibilities include responding to user inquiries, troubleshooting and resolving issues, implementing system enhancements, and supporting the ongoing evolution of mission-focused applications.

In addition to sustaining the current production environment, the successful candidate will play a key role in the modernization effort to develop and transition users to a next-generation application, while supporting the planned decommissioning of the legacy platform. This position offers a unique opportunity to contribute to both operational support and the future architecture of a critical IC mission system. HOW A SENIOR SOFTWARE ENGINEER WILL MAKE AN IMPACT:

• Provide Operations and Maintenance (O&M) support for mission-critical applications used by Intelligence Community customers.
• Respond to user-reported issues and questions, troubleshoot problems, and implement solutions in a timely manner.
• Design, develop, test, and deploy software enhancements and new capabilities.
• Collaborate with stakeholders to gather requirements and translate business needs into technical solutions.
• Participate in Agile ceremonies including sprint planning, daily standups, reviews, and retrospectives.
• Maintain and improve application performance, reliability, and security.
• Develop and maintain technical documentation and system artifacts for legacy system.
• Support application integrations and data exchange with external systems and services.
• Work closely with team members to continuously improve development, deployment, and support processes.
• Support the lifecycle management of both legacy and modernized applications, ensuring continuity of operations throughout migration efforts.
• Contribute to the design, development, testing, and deployment of a new application while maintaining and enhancing the existing production system.
• Assist with planning and executing the decommissioning of legacy application components, services, and infrastructure.

REQUIRED SKILLS AND EXPERIENCE

• Self-starter mentality with a strong desire to learn and deliver solutions efficiently to customers.
• Strong understanding of software design fundamentals and object-oriented programming principles.
• Experience applying modern software engineering principles including SOLID, DRY, KISS, and YAGNI.
• Experience working in Linux-based development environments.
• Understanding of Git/GitHub source control and Agile development methodologies.
• Experience architecting and developing web applications.
• Experience developing applications using Ruby on Rails.
• Experience with JavaScript frameworks such as ExtJS and/or VueJS.
• Experience utilizing Bootstrap for responsive user interface development.
• Experience deploying and supporting solutions in Amazon Web Services (AWS).

DESIRED SKILLS

• AWS certifications.
• Experience integrating and unifying records from multiple data sources.
• Experience developing applications that consume and integrate external APIs.
• Experience supporting applications in a secure Intelligence Community environment.
• Understanding of DevSecOps practices and CI/CD pipelines.

WHAT YOU'LL NEED TO SUCCEED: Education

• Bachelor's degree in Computer Science, Software Engineering, Information Systems, or a related technical discipline. Equivalent combinations of education, technical certifications, training, and experience will be considered.

• 6+ years of software development experience.
• Experience supporting enterprise web applications in production environments.
• Experience working within Agile software development teams.

• Active TS/SCI with Polygraphrequired.
• U.S. Citizenship required.

• Chantilly, VA or McLean, VA
• On customer site 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