Allen Integrated SolutionsVerified Source

Senior .NET Developer, C# & SDLC Expertise

Onsite · Washington, District of Columbia
Posted August 14, 2026
full-time

Overview

Lead the design and development of .NET applications at scale using MS .NET, C#, MVC 4+ and IIS within a DoD context. Collaborate with cross functional teams to deliver secure software solutions while mentoring junior engineers. Work on SDLC processes, testing strategies, and defect management to ensure high quality releases. This role is onsite in Fort Belvoir with TS/SCI w/CI Poly required and opportunities to grow into broader architecture responsibilities.

What You'll Do10

  • 1Build robust .NET applications and services using C# and MVC 4+ on IIS
  • 2Design and implement secure software solutions following SDLC best practices and documentation standards
  • 3Lead unit, integration, system, and user acceptance testing to verify functionality and performance
  • 4Mentor junior engineers on coding standards, testing practices, and defect prevention
  • 5Collaborate with stakeholders to translate requirements into technical designs and task plans
  • 6Ship features with measurable outcomes in release cycles and coordinate with project managers
  • 7Debug complex issues across full stack and optimize performance
  • 8Maintain and improve existing codebase with emphasis on reliability and security
  • 9Document software defects using bug tracking systems and report findings to teams
  • 10Ensure compliance with DoD 8140.03 IAT II and maintain required clearances

Requirements6

  • 1Eight years of experience in .NET development including MS .NET, C#, MVC 4+, and IIS for Windows Server web development
  • 2Five years of experience with SDLC processes and software development testing (Unit, System, Functional, UAT)
  • 3Five years of experience with SQL database development and stored procedures
  • 4Five years of experience mentoring junior personnel on proper practices and procedures
  • 5Five years of experience documenting software defects using a bug tracking system and reporting defects to software developers and project managers
  • 6Certifications: TS/SCI clearance with SBI and ability to attain SI, TK, G, HCS, and NATO Secret clearance; DoD 8140.03 IAT II / Intermediate certification

Salary Insight

Salary not disclosed in listing

Location

Typeonsite
LocationWashington, District of Columbia

Required Skills

.NETC#MVCIISSDLCUnit TestingSystem TestingFunctional TestingUser Acceptance TestingSQLStored ProceduresMentoringBug TrackingTS/SCI ClearanceDoD 8140.03 IAT Level II
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