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# Senior .NET Developer

- **Company:** Koniag Services, Inc.
- **Location:** Washington, DC, United States
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** ASP.NET, HTML, JavaScript (Programming Language), .NET Framework, Artificial Intelligence, Automation of Tests, Microsoft Azure, C Sharp (Programming Language), Cascading Style Sheets (CSS), Entity Framework, Model View Controller (MVC), OAuth, Oracle (Applications), Regression Testing, Release Management, Openid Connect, OpenAI, Single Sign-On, Software Engineering, Product Software Implementation Methods, Systems Integration, RxJS, GitHub Copilot, Large Language Models, Multi-Agent Systems, Asp.net Web Api, Git, Xunit, HR Software, Build Management, AI Platforms, AngularJS, Information Technology, People Soft, Playwright, Software Version Control, Web Api
- **Published:** October 23, 2026
- **Apply:** https://www.clearancejobs.com/jobs/9261572/senior-net-developer

## About the Role

* Active Secret security clearance (U.S. citizenship required)
 * Bachelor's degree in Computer Science or related field; 4 additional years of experience in lieu of degree
 * Minimum of 7 years of total software development experience, including at least 6 years in .NET development with strong proficiency in C#, ASP.NET (Web Forms, MVC, and Web API), and both .NET Framework and modern .NET
 * Experience designing and building enterprise ASP.NET Web APIs secured with OAuth 2.0 / OpenID Connect
 * Working knowledge of Oracle databases and SQL, including ODP.NET or Entity Framework with Oracle
 * Demonstrated experience building or integrating AI features in applications (LLM APIs, agents, or similar)
 * Experience using GitHub Copilot or a similar AI coding assistant, and experience using AI for regression testing
 * Experience using Azure DevOps for Git source control, build and release pipelines, and deployments
 * Experience supporting production applications: troubleshooting, root-cause analysis, and fixes under change control
 * Familiarity with JavaScript, HTML, and CSS
 * Strong problem-solving, communication, and interpersonal skills

Preferred skills and experience:

 * HR knowledge, especially federal HR: OPM position classification, GS grades, position descriptions
 * Experience with Duende IdentityServer, token-based authentication, and single sign-on
 * Experience with Angular (standalone components, reactive forms, RxJS)
 * Experience building MCP servers, multi-agent systems, or Azure OpenAI / Microsoft AI solutions in .NET
 * Experience with performing automated testing with Playwright, xUnit, or similar tools

## Description

The successful candidate will lead the Design, development, and implementation of software solutions using .NET Framework, ASP.NET Web API, Angular, and Oracle and will lead the operations and maintenance (O&M) of a Federal HR position classification application. The candidate will support and lead (as needed) new AI-assisted development, including tools that analyze position descriptions and support classification decisions., * Maintain, enhance and troubleshoot applications across its full stack: .NET Framework, ASP.NET Web API, Angular, and Oracle

 * Develop and maintain enterprise ASP.NET Web APIs that serve the classification application and related HR applications
 * Support integration with PeopleSoft HR data (organizational hierarchies, position and locality data)
 * Maintain automated regression tests (e.g., Playwright) and technical documentation for the application stack
 * Prepare Implementation guides and technical documentation
 * Maintain and upgrade the Duende IdentityServer (security token service) host, including OAuth 2.0 / OpenID Connect clients, scopes, and certificates
 * Design and build AI-assisted applications in .NET, such as tools that analyze position descriptions and support classification determinations