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Mid-Level Software Developer C#.NET ๐Ÿ†

3Si Security Systems
Full Timemid
Ashburn, Virginia, US$78k โ€“ $118kPosted March 20, 2026

Salary Context

This role offers $78kโ€“$118k. The median for Mid-level lifecycle roles is $97kโ€“$135k (based on 121 listings). 16% below median.

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GitJiraREST

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Job Description

Mid-Level Software Developer ๐Ÿ’ฐ Salary: $78,000 - 118,000 per year

At 3Si Security Systems we are looking for a C#.NET engineer!

๐Ÿ› ๏ธ Our tech stack:

.NET Framework, C#, Git, HTTP, Support, JIRA, Network, REST, Security, Telerik, Visual Studio, WPF, Windows, UX UI Design, ASP.NET, .NET

๐Ÿ“ Rquirements:

  • Strong understanding of full-stack development practices
  • Proficiency in C# and the .NET framework
  • Experience with Windows Presentation Foundation (WPF)
  • Knowledge of software development best practices and secure coding techniques
  • Ability to work with RESTful APIs and HTTP network technologies
  • Skilled in using Visual Studio, Git, and Jira
  • Strong problem-solving and analytical abilities
  • Effective communication and collaboration skills
  • Ability to work independently or within a team environment
  • Bachelors degree in Computer Science, Information Technology, Software Engineering, or a related technical field
  • Equivalent professional experience may be considered in lieu of formal education
  • Associate degree in a technical discipline combined with relevant experience and/or industry certifications may also be considered
  • At least 5 years of related software development experience
  • Minimum of 3 years of hands-on experience in C#/.NET development
  • Experience with reusable C# library development and version-controlled environments

๐Ÿ‘ฉโ€๐Ÿ’ป๐Ÿ‘จโ€๐Ÿ’ป Your responsibilities are:

  • Participate in full software development lifecycle activities, including design, development, testing, debugging, and implementation
  • Define and document functional requirements based on stakeholder feedback
  • Design and develop scalable software solutions utilizing C# and .NET
  • Collaborate with peers and cross-functional teams to ensure technical alignment with project objectives
  • Employ development tools such as Visual Studio, Git, and Jira
  • Work with technologies including REST/ServiceStack, WPF, and Progress/Telerik UI Toolkit
  • Support and maintain client and server applications using REST and HTTPS protocols
  • Undertake additional tasks as required to support the companys mission and project goals

View this job and over 500 other transparent jobs with salaries (๐Ÿ’ฐ๐Ÿ’ฐ๐Ÿ’ฐ) & tech stacks (๐Ÿ› ๏ธ) on DevITJobs

Category: C#.NET Developer / Engineer

Location address: Red Rum Drive 21660, Arlington, United States

Salary: $78,000 - 118,000 per year

Benefits & perks that we offer:

3Si Security Systems - More about us and the role:

At 3Si, our mission is to enhance safety across the globe through innovative security technology. We are a leading entity in the field, enabling businesses and law enforcement to effectively counter and respond to crime with our proven solutions and strong partnerships. With over 100 years of collective experience, our specialized focus on GPS tracking, video surveillance, and integrated response technologies is aimed at various sectors, including retail and finance. We foster a collaborative, purpose-driven culture, offering a hybrid work environment, competitive benefits, and opportunities for personal and professional growth. Join us in our commitment to making a meaningful impact in our communities.

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