Top C# Jobs in Washington, DC

Design, build, test, and maintain tax-focused software solutions using Java, Python, C# and JavaScript. Apply ATDD and CI/CD, create APIs and microservices, perform code reviews and debugging, manage project delivery, and collaborate with cross-functional teams to improve business processes and client outcomes.

As a Mixed Reality Developer, you will create high-performance Mixed Reality applications, collaborating with cross-discipline teams to deliver innovative solutions for mission-critical operations.

Develop, enhance, and maintain backend web applications and services using C#/.NET. Implement features with ASP.NET, Entity Framework, and SQL Server; write unit and integration tests; perform troubleshooting, code reviews, vulnerability remediation, and O&M tasks while collaborating with senior engineers and cross-functional teams.

Provide O&M and development support for a production .NET web application. Gather and analyze requirements, design solution architecture, build and upgrade full-stack features, improve performance, and support the application lifecycle while collaborating with government and contractor teams.

Lead the design and development of Windows desktop applications, focusing on architecture, accessibility, and best practices, ensuring quality and performance across releases.

Develop and maintain a custom Microsoft Dynamics 365 solution for the U.S. Treasury: configure forms, update logic and flows, build custom C# workflows, customize Dynamics portals with JavaScript, assist system testing and develop the DevOps pipeline.

Design, build, and maintain cloud-native full-stack applications and backend services that support investment risk analysis. Own end-to-end delivery, contribute to architecture, apply automated testing and CI/CD, collaborate with stakeholders, reduce technical debt, and ensure reliable, observable data and analytics for portfolio risk and simulations.

Senior full‑stack .NET engineer responsible for design through production of secure, scalable web applications. Work includes C#/.NET backend, WPF/WCF components, REST APIs, frontend JS/HTML/CSS, cloud migration, code reviews, testing, and performance/security analysis. Expected to lead architecture, collaborate with teams, and apply SOLID, OOP, and SOA principles.

Develop and maintain Ruby and Rails applications, write Bash scripts, troubleshoot performance and multithreading issues, optimize SQL/MySQL queries, administer Unix/Linux/Solaris servers, and collaborate in Agile teams. Participate in API and SOA development and use source control (SVN/Git).

Design, build, test, and deploy wargame-specific software and integrated GIS-based common operating picture tools. Create multi-user front-end interfaces, integrate and dynamically update databases, and support planning, execution, and post-game analysis for HQ USAF wargames.

Lead design, development, and management of software and database applications supporting USAF wargaming. Provide systems engineering, supervise developers and IT staff, manage LAN and ISSM/ISSO functions, advise leadership, and improve wargame infrastructure and post-game analysis.

Designs, develops, and executes IT solutions and applications to support HQ USAF wargames. Deploys and manages LAN server suites for hundreds of clients, maintains hardware/software/network architectures, provides system administration and security (ISSM/ISSO) support, and develops participant training and post-game analysis.

Design, build, test, deploy, and support software for USAF wargaming; develop UI/UX (including map interfaces), integrate M&S and databases, support systems engineering, and employ multi-agent/LLM-based tools like MAGE during planning and execution phases.

The Sailpoint Consultant will maintain and support SailPoint IIQ infrastructure, troubleshoot issues, develop scripts, and assist project teams with identity and access solutions.

Design and develop solutions using Power Apps and Power Automate. Lead design sessions, implement data models, and manage solution lifecycles. Mentor junior developers and ensure adherence to governance best practices.

Design, build, and scale the Substantiation Platform for validating and reconciling financial data. Provide architectural leadership and mentor engineers.

The SharePoint Consultant will design, develop, customize, and integrate SharePoint web portals, supporting applications development and workflows for clients.

Maintain and support mission-critical .NET web applications backed by an Oracle database. Fix bugs, implement enhancements, manage version control and deployment pipelines, write/execute DDL/DML, produce documentation, and work within an Agile team while providing production support.

Design and implement runtime protocols, formats, and systems to capture, serialize, stream, and replay interactive 3D content across engines. Own C++ runtime and C# APIs across editor, build, simulation, streaming, and playback. Optimize for low-latency, determinism, memory and bandwidth constraints, and build AI interfaces for inspecting and invoking engine state.

Design, implement, deploy, and operate large-scale distributed backend systems and Azure infrastructure for AI-driven insights. Apply generative AI/ML, build IaC and CI/CD pipelines, support live-site operations, and execute onboarding and operational tasks for GCC‑High/DoD environments while ensuring security, observability, and cross-team collaboration.

Lead design, build, and operation of large-scale, distributed, full-stack systems. Drive technical initiatives, deliver iterative customer-focused releases, improve maintainability and performance, mentor engineers, research and adopt new technologies, and collaborate across teams to meet enterprise needs.

Lead technical planning and execution of AWS-to-Azure cloud migration and enterprise application modernization. Design Azure architectures, develop migration roadmaps, guide engineering teams, ensure security and compliance, produce technical documentation, and support executive briefings and incident restoration.

As a Senior Software Engineer, you'll design architecture, mentor engineers, and drive the adoption of AI practices to enhance development workflows and system reliability.

Design, develop, configure and administer SharePoint 2010 farm solutions including sites, templates, workflows, web parts and custom code (C#/ASP.NET). Lead migrations from PlumTree, configure service applications (Search, Excel Services, PerformancePoint), use PowerShell for administration, and coordinate deployments across development, test and production environments.

As a Software Engineer, you will design and build backend services for Relativity's generative AI platform, focusing on scalability and reliability in distributed systems.