Senior Software Engineer — TS/SCI Clearance (Onsite MD)

System One, Inc.; Gaithersburg (MD); On-site; USD 140,000 - 180,000; Full time

Job summary

System One, Inc. is seeking a Senior Software Engineer in Gaithersburg, MD to design, develop, and maintain mission-critical enterprise applications in a hands-on Agile environment. The role requires active Top Secret/SCI clearance with polygraph readiness and extensive experience in Java, C#, Python, or C++.

You will collaborate with product owners, architects, and DevSecOps teams to build secure, scalable software, and to support CI/CD pipelines and automated deployments in an onsite setting.

Qualifications

• Active Top Secret/SCI clearance
• polygraph examination required
• 8–12 years of relevant software experience with a bachelor’s degree, or 6–10 years with a master’s degree
• 8+ years of professional software development experience
• Experience with at least one OOP language (Java/C#/Python/C++)
• Experience building web-based enterprise software and RESTful APIs
• Experience with relational/NoSQL databases and Agile/Scrum environments
• Strong debugging, analytical, and communication skills

Responsibilities

• Design, develop, test, deploy, and maintain enterprise software applications
• Write clean, secure, well-documented code following best practices
• Design and implement RESTful APIs and microservices
• Participate in Agile ceremonies and collaborate across teams
• Develop automated tests for unit, integration, and end-to-end scenarios
• Conduct code reviews and mentor junior developers
• Troubleshoot complex issues and perform root cause analysis
• Support CI/CD pipelines and automated deployments
• Optimize performance, scalability, and security
• Contribute to architecture discussions and technical roadmaps
• Support production deployments in mission-critical environments

Skills

Java

C#

Python

C++

Education

Bachelor’s degree in Computer Science or related field

Master’s degree in Computer Science or related field

Tools

Git

Docker

Kubernetes

Terraform

Job description

System One, Inc. is seeking a Senior Software Engineer in Gaithersburg, MD to design, develop, and maintain mission-critical enterprise applications in a hands-on Agile environment. The role requires active Top Secret/SCI clearance with polygraph readiness and extensive experience in Java, C#, Python, or C++.

You will collaborate with product owners, architects, and DevSecOps teams to build secure, scalable software, and to support CI/CD pipelines and automated deployments in an onsite setting.