Lead .Net Developer (Secret clearance)
Reston, VA
Experience: 15
Education: BA, BS
Category: Information Technology
Contractor Work Model: Onsite
Brand: System One
Job ID: 379173
Date Posted: 08/28/2026
Shortcut: http://jobs.systemone.com/p4Pt8U
Lead .Net Developer
Arlington, VA or Merrifield, VA - ONSITE
Secret Clearance is required to start
Must be able to obtain DEA clearance – 2-6 month process
Responsibilities:
• Lead a team of 5-7 developers in support of the mission with an ability to guide them on technical decisions, best practices, and team efficiencies
• Lead technical planning meetings
• Conduct peer code reviews and final code reviews
• Demonstrate soft skills in terms of professionalism, conduct and execution in a client-facing role
• Have an ability to effectively collaborate with leadership and customers
• Ensure the Requirements Analysts data is accurately reflected in the appropriate system of record
• Ensure quality and integrity of the software prior to it reaching production
• Apply modern software development techniques for a modular system
• Have an ability to learn new technologies as they are introduced, and the software applications and environment evolves
• Support modernization of software development practices
• Significant recent C# development experience.
• Significant recent Java Script development experience.
• Significant development experience with Cascading System Sheets (CSS).
• Experience with relational data models and SQL.
• Experience with XML and programming libraries for XML manipulation.
• Agile project and development experience utilizing Team Foundation Server.
• Ability to quickly deliver small projects, and to frequently transition between projects and applications.
• Experience in packaging and delivering software and documentation to a production environment.
Requirements:
• Experience as a developer in a software environment that supported more than 10,000 users and a Relational Database Management Systems (RDBMS) with more than 250 tables and 1 million total rows.
• Experience in at least one software development environment with a minimum of 1,000 automated unit tests.
• Recent development experience (at least 5+ years) with ASP.NET MVC based web development using Visual Studio..
• Must have an Active Secret clearance in order to view, discuss, and handle classified data in support of applications.
Experience/Education:
• Minimum 15 years of web development experience.
• Minimum 5 year of .Net Core/Standard development experience.
• Minimum 10 years of ASP.Net C# MVC based web development experience using Visual Studio 2017 or higher.
• Minimum 8 years of experience with Agile development methodologies including participation in Sprints, Backlog grooming, and Agile Ceremonies.
• Bachelor’s degree in a related technical field, desired
Nice to Have:
• 5+ years of e-GIS experience, including:
• Geolocation from addresses to Lat/Long.
• Utilizing mapping software in a web context (e.g., Open Street Maps or similar).
• Displaying and placing marking pins on satellite imagery.
• Leveraging distance measurement tools on maps in a web browser.
System One, and its subsidiaries including Joulé and Mountain Ltd., are leaders in delivering outsourced services and workforce solutions across North America. We help clients get work done more efficiently and economically, without compromising quality. System One not only serves as a valued partner for our clients, but we offer eligible employees health and welfare benefits coverage options including medical, dental, vision, spending accounts, life insurance, voluntary plans, as well as participation in a 401(k) plan.
System One is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, age, national origin, disability, family care or medical leave status, genetic information, veteran status, marital status, or any other characteristic protected by applicable federal, state, or local law.
#M1
#LI-VH1
Ref: #851-Rockville-S1
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