Top .NET Developer Jobs in Seattle, WA

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.

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.

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.

Build and maintain C#/.NET backend services, APIs, web applications, ERP and billing features, and financial integrations. Modernize legacy .NET Framework applications onto Azure, optimize SQL Server and Azure SQL data access, create automated tests, support CI/CD, instrument production systems, and implement secure authentication and configuration. Troubleshoot application, database, and hosting issues while collaborating with DevOps, architects, product leaders, and stakeholders.

Lead design and delivery of scalable full‑stack, cloud‑native applications. Drive architecture, AI‑assisted tooling, DevOps and observability practices, implement microservices/APIs, mentor engineers, and publish documentation and runbooks to ensure reliability and operational excellence.

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.

Designs, develops, and maintains scalable distributed systems and full-stack applications using ReactJS and .NET or Java. Builds RESTful APIs and microservices, manages SQL and NoSQL data, and applies cloud, Docker, Kubernetes, and CI/CD practices. Collaborates with stakeholders and cross-functional teams, leads design reviews and code reviews, mentors junior engineers, documents systems, and supports critical applications through on-call rotations.

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.

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.

Build and maintain scalable, cloud-native APIs and high-value core system components using .NET and related technologies. Lead software architecture and testing discussions, enhance core offerings, collaborate cross-functionally, and ensure quality through code reviews, unit testing, functional testing, telemetry, and performance tuning. Mentor teammates and contribute to continuous technical and process improvement.

Lead development of secure, scalable digital banking software across front-end and backend systems. Design Angular or React applications, build APIs, optimize SQL performance, integrate third-party platforms, improve code quality, implement testing strategies, and mentor engineers. Collaborate with cross-functional teams in an Agile environment while supporting cloud-native practices, regulatory compliance, and continuous product improvement.

Owns the design, development, testing, deployment, and maintenance of production software. Builds C#/.NET backend services, Angular web applications, and .NET MAUI mobile apps; optimizes SQL Server databases; resolves production issues; improves reliability, security, performance, and observability; writes tests and documentation; participates in code reviews; and translates ambiguous business needs into maintainable technical solutions.

Build scalable backend-heavy services and applications using C# and .NET, while contributing to Angular and TypeScript UI development. Design and develop REST APIs and microservices, work with relational databases, implement automated testing and CI/CD, and ensure system security, scalability, and performance. Preferred work includes event-driven architectures, messaging systems, NoSQL databases, caching, search technologies, and mentoring engineers or leading technical initiatives.

Leads end-to-end modernization from a monolith to microservices, including legacy analysis, architecture, estimation, data migration, deployment, and production support. Guides .NET services, databases, messaging, containerization, and frontend integrations. Acts as the technical escalation point for complex issues while improving Jira tracking, estimation accuracy, QA collaboration, release predictability, and engineering processes. Manages and develops the team through one-on-ones, performance reviews, feedback, and career-focused objectives.

Develop, design, modify, test and implement ASP.NET applications using MVVM, UWP and WPF. Collaborate in Agile Scrum, provide estimates, participate in code reviews, and resolve production issues.

Develop web applications using AngularJS, ASP.NET, C#, and documentation. Collaborate with teams to solve problems and ensure high quality.

The role involves developing applications using .Net technologies and managing testing for web services and applications.

Develop large scale production websites using ASP.NET MVC, Web APIs, C#, and front-end technologies like HTML5 and JavaScript.

The role involves enhancing, developing, and maintaining .NET applications for over 6 years. Communication skills are essential.

Develop and maintain applications using .Net C# and SQL, with a focus on Azure deployments, while communicating effectively and multitasking under pressure.

The .Net Developer will develop applications using .Net C#, SQL, and Azure, requiring strong communication skills and the ability to work independently.

The .NET Developer will build applications on Azure using .NET C# and SQL. Communication skills and multitasking are essential.

Seeking a Jr. .Net Developer with hands-on C# experience and SQL Server knowledge. Familiarity with Azure, ASP.NET, and web services is preferred.