Job Information
Robert Half Senior C# Developer in Washington, District Of Columbia
Description
We are seeking a Senior C# / .NET Developer to support full‑lifecycle development of custom enterprise applications in a mission‑critical, highly visible environment. This role is ideal for a seasoned developer who is customer‑focused, self‑directed, and comfortable working onsite in a collaborative setting.
You will work closely with program leadership, business analysts, and engineering teams to translate business and mission requirements into high‑quality technical solutions. Strong communication skills and the ability to operate with limited supervision are essential.
Key Responsibilities
Design, develop, and test high‑quality applications using C# and the .NET / .NET Core ecosystem
Support the full software development lifecycle, from requirements through deployment and operational support
Collaborate with program managers, business analysts, and engineers to translate requirements into technical solutions
Lead or contribute to architecture and technical design decisions
Troubleshoot, debug, and optimize application performance
Provide operational support and monitoring for deployed applications
Develop and maintain technical and system documentation
Participate in Agile development processes and ceremonies
Interface directly with customers to understand needs and ensure timely, effective delivery
Requirements
Required Qualifications
Bachelor’s degree with 12–15 years of relevant experience
or Master’s degree with 10–13 years of relevant experience
Ability to obtain and maintain a Public Trust clearance
Strong proficiency in C# and .NET / .NET Core
Experience building and maintaining backend services and APIs
Solid understanding of object‑oriented design principles and patterns
Experience with relational databases (Oracle)
Experience using GitLab or similar source control tools
Ability to write and maintain clear technical documentation
Strong verbal and written communication skills
Agile development experience
Proven experience working directly with customers or stakeholders
•Preferred Qualifications
Experience with ASP.NET Core, REST APIs, and MVC architecture
Familiarity with CI/CD pipelines and automated testing
Exposure to modern frontend frameworks (React, Angular, etc.)
Experience troubleshooting production or operational issues
Prior experience in regulated or government‑focused environments
Existing Public Trust clearance (strong plus)
Technology Doesn't Change the World, People Do.®
Robert Half is the world’s first and largest specialized talent solutions firm that connects highly qualified job seekers to opportunities at great companies. We offer contract, temporary and permanent placement solutions for finance and accounting, technology, marketing and creative, legal, and administrative and customer support roles.
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