Top .NET Developer Jobs in Washington, DC

Develops, enhances, maintains, and supports enterprise web applications and services using C#, ASP.NET, and .NET Core. Responsibilities include translating requirements into technical solutions, reviewing and improving code, troubleshooting production issues, collaborating with multidisciplinary teams, and supporting builds, testing, releases, deployments, Agile sprints, documentation, and application modernization.

Develop, test, debug, enhance, and maintain software applications using .NET, C#, SQL, JavaScript, and HTML. Integrate designs and specifications, resolve hardware and software interface issues, research emerging technologies, create technical documentation, troubleshoot application problems, support customers, and report on project progress. The role requires an active Top Secret clearance with SCI eligibility and is performed onsite in Washington, DC.

Develop and maintain ASP.NET and .NET Core web applications and services. Translate business requirements into maintainable software, troubleshoot defects, test changes, support deployments, document technical work, and coordinate with business analysts, database staff, infrastructure teams, and customer stakeholders. The role is full-time onsite in Washington, D.C., may require occasional overtime or evening and weekend work, and is contingent on contract award.

Develop and maintain full-stack web applications using .NET and React. Responsibilities include designing, coding, testing, deploying, and troubleshooting front-end and back-end components; implementing scalable APIs and application architecture; conducting unit, integration, and system testing; participating in code reviews; collaborating with cross-functional teams; and contributing to software development lifecycle improvements. The role requires active Top Secret clearance and at least eight years of experience.

Develop, test, deploy, and support .NET applications, Azure services, and Dataverse model-driven Power Apps. Build containerized microservices, plugins, Power Automate flows, Power BI reports, and dashboards. Analyze existing applications, recommend improvements, write automated tests, participate in Agile planning and client sessions, and maintain development, testing, and production environments.

Designs, develops, tests, deploys, and manages .NET full-stack applications supporting FBI IT infrastructure. Responsibilities include integrating third-party components, enhancing existing code, automating operations and maintenance, large-scale data processing, statistical modeling, advanced analytics, and full software development lifecycle participation. The role also conducts architecture reviews, milestone reviews, resource estimation, process improvement, quality assurance, and team mentoring.

Design, develop, test, secure, and maintain enterprise applications and APIs using C# and modern .NET. Build database solutions, RESTful integrations, automated tests, and CI/CD pipelines while supporting Agile and DevSecOps delivery. Modernize legacy applications, troubleshoot production issues, conduct code and design reviews, and remediate security findings. The role requires an active DoD Secret clearance and U.S. citizenship and is remote within the United States during Pacific Standard Time hours.

Modernize legacy Java and .NET applications by analyzing dependencies, preserving APIs and business behavior, building compatibility adapters, refactoring services, and supporting migration, testing, deployment, cutover, and retirement. The role also requires secure DevSecOps practices, documentation, production troubleshooting, stakeholder communication, and protection of classified and Controlled Unclassified Information in government environments.

Own and evolve Swyfft’s partner-facing insurance API, including resource design, versioning, backward compatibility, authentication, rate limiting, error handling, metrics, documentation, and contract testing. Build production C# code, maintain the translation layer between public APIs and internal systems, support partner integrations, and collaborate with QA and product. The role requires substantial public API experience, strong API security and multi-tenancy knowledge, and fluency in C#, ASP.NET Core, SQL Server, and Azure.

Develop and maintain full-stack web applications using .NET, ASP.NET, React, and related technologies. Design front-end and back-end components, write and test scalable code, troubleshoot issues, participate in code reviews, and collaborate with cross-functional teams throughout the software development lifecycle. The role is onsite at a government facility in Washington, D.C., and requires an active Top Secret clearance with SCI and CI Poly eligibility.

Develop and maintain full-stack web applications using .NET and React. Design front-end and back-end components, write scalable code, conduct testing, troubleshoot issues, participate in code reviews, and collaborate with cross-functional teams throughout the software development lifecycle. The role requires active TS/SCI clearance, U.S. citizenship, a bachelor’s degree, and at least eight years of experience.

Develop and maintain full-stack web applications using React, .NET, and related technologies. Design front-end and back-end components, write scalable code, conduct testing, troubleshoot issues, participate in code reviews, and support the full software development lifecycle. Collaborate with cross-functional teams and clients while applying secure coding, architectural patterns, cloud services, and DevOps practices. The role also includes mentoring, technical communication, and contributing to continuous process improvement.

Designs, develops, maintains, and troubleshoots scalable software applications using .NET, SQL Server, UI frameworks, and cloud technologies. Collaborates with product owners, developers, testers, and technology leads; participates in code reviews; writes documented code; and improves software development practices.

Build and support complex features across C#/.NET back-end services and React front ends. Responsibilities include technical design, API and data modeling, secure and tested coding, production troubleshooting, code reviews, mentoring, documentation, and improving engineering practices. Collaborate with Product, QA, DevOps, Technical Leads, and architecture teams while balancing delivery, maintainability, performance, accessibility, observability, and security.

Develop, test, maintain, and support secure, scalable full-stack .NET applications in an Agile/Scrum environment. Responsibilities include API and database development, technical documentation, code and design reviews, SDLC compliance, security and audit adherence, collaboration with architects and business partners, mentoring junior engineers, leading project delivery, and participating in on-call support and occasional travel.

Leads full-stack development, maintenance, troubleshooting, and implementation of a federal HR position classification application. Develops .NET APIs, integrates PeopleSoft and Oracle data, maintains authentication services, automated tests, documentation, and Azure DevOps pipelines. Builds AI-assisted applications using LLMs and related technologies while supporting production operations, root-cause analysis, and controlled releases.

Leads architecture and development of complex backend services for a commercial health plan platform. Designs .NET Core and Azure systems, develops claims, eligibility, and benefits functionality, manages healthcare data integrations, and owns cloud infrastructure and CI/CD architecture. Provides technical leadership through code reviews, testing standards, mentoring, and architecture decisions while ensuring performance, reliability, security, and regulatory compliance.

Develop and optimize Microsoft .NET applications, legacy systems, and microservices with a focus on performance, scalability, reliability, and observability. Responsibilities include code reviews, performance testing, CI/CD integration, architecture and sprint delivery, legacy code and SQL tuning, cloud application deployment on Azure, automated testing, and resolving customer issues. The developer collaborates with architects, QA, technical support, and cross-functional teams using SAFe Agile practices.

Develop and maintain OneStream applications using .NET for federal financial management, reporting, planning, and budget execution. Build business rules, data management solutions, workflows, and integrations with financial systems. Translate business requirements into technical designs, support testing and deployment, troubleshoot issues, and collaborate with finance stakeholders and technical teams. The role requires strong .NET, VB.NET, SQL, data modeling, and financial systems experience, along with eligibility to obtain a federal security clearance.

Senior .NET Software Engineer responsible for end-to-end software development using Microsoft technologies. Requires extensive experience in SDLC, design principles, technical documentation, web application development with .NET, Agile/SCRUM, Entity Framework, database design, and version control. Familiarity with project tools JIRA, TEMPO, Bitbucket, and Confluence preferred.

Senior .NET Web App Developer responsible for designing and building .NET web applications, implementing Oracle PL/SQL solutions, using Entity Framework and Blazor, applying design principles, producing technical documentation, performing performance tuning, and collaborating in Scrum/Agile teams with Bitbucket, JIRA, Tempo, and Confluence.

Develop and maintain web-based applications using .NET/C#, JavaScript, HTML/CSS, SQL and Oracle/SQL Server. Perform root cause analysis, collaborate with teams for requirements, follow Agile SDLC, present change demonstrations, and use Azure DevOps/Jira for lifecycle management. Implement and maintain Blazor components.

Design, build, and maintain production-grade .NET web applications and APIs on Azure. Own full-stack delivery from data models and SQL to front-end components, CI/CD, testing, and architecture. Collaborate with product and delivery teams, participate in code reviews, and ensure secure, observable, well-tested services.

Develop and maintain C#/.NET applications throughout the software development lifecycle, including requirements analysis, architecture, coding, testing, debugging, integration, and configuration. Collaborate with clients and team members to prioritize development backlogs and plan releases. Build reliable, reusable code, analyze system requirements, and support applications using .NET technologies, SQL, APIs, JavaScript, and related systems.

Leads the design, development, and implementation of full-stack applications using C#, .NET, Angular, Azure, and SQL Server. Collaborates with cross-functional teams, ensures application security, performance, and scalability, applies Git-based version control practices, mentors developers, and stays current with emerging technologies.