Application developer Security Clearance

Position: Application developer with Security Clearance
Job Title:

Application Developer

Location:

Reston, VA Clearance: TS/SCI with Full Scope Polygraph (Required) Company:
Quantum Science Solutions (QSS) Compensation:
Open Rate

Position Overview
Quantum Science Solutions (QSS) is seeking a cleared and local Application Developer to support a mission-critical federal program in the Reston area. This role involves maintaining existing legacy applications and assisting in the transition to a modernized system architecture that enhances enterprise performance, scalability, and security. The successful candidate will bring strong full-stack and backend development expertise, proficiency in Java, RDBMS support, and a solid understanding of API creation and integration.

This position requires hands-on technical problem-solving and close collaboration within Agile teams to deliver high-quality, secure, and reliable solutions.

Key Responsibilities

• Maintain, enhance, and support legacy applications while facilitating transition to new architecture.

• Develop and maintain backend services, APIs, and data integrations.

• Provide RDBMS (Relational Database Management System) support including performance tuning and data modeling.

• Utilize Java for backend development and support system modernization efforts.

• Apply strong troubleshooting and problem-solving skills to address issues across all application layers.

• Collaborate within an Agile/Scrum environment alongside developers, testers, and system engineers.

• Document technical system architecture and application design.

• Manage source code using Git (Git Hub, Git Lab, etc.). Mandatory Skills

• Minimum 5 years of experience in Full Stack Development.

• Minimum 3 years of demonstrated RDBMS support experience.

• Proven Java development experience.

• Strong troubleshooting and debugging skills.

• Demonstrated experience in backend development and API creation.

• Experience working within an Agile development environment.

• Ability to document technical system architectures and processes.

• Proficiency with Git (e.g., Git Hub, Git Lab). Preferred Skills

• Experience with C# and legacy system development.

• Experience integrating applications with Geographic Information Systems (GIS). Education
• Bachelor’s degree in Computer Science, Computer Engineering, Computer Information Systems, Computer Systems Engineering
• Equivalent experience may be substituted on a year-for-year basis. Why QSS? At QSS, you’re not just filling a role, you’re shaping mission-critical solutions that keep our nation secure. We invest in your growth, foster innovation, and reward technical excellence. Benefits include:
• Competitive compensation with annual performance bonuses
• Premium Medical, Dental & Vision coverage
• Generous PTO plus Federal Holidays
• 401(k) with company match
• Opportunities for continuous learning and skill development