Top C# Jobs in Seattle, WA

Design, refactor, and build high-performance C++ core infrastructure for vehicle dynamics and Starlink simulations. Lead Monte Carlo and HPC simulation development, optimize performance and reliability, create testing/HITL frameworks and visualization tools, and collaborate cross-functionally to model multi-body physics, environmental effects, and hardware behavior while improving CI, profiling, and testability.

Lead technical direction for a major product domain, reduce architectural debt, mentor engineers, standardize AI-agent workflows, and design scalable backend solutions integrating LLMs and cloud services. Drive cross-team RFCs, cookbook standards, and adopt agentic AI tooling while balancing security, quality, and delivery.

Design and optimize high-performance C++/CUDA libraries for GPU-based data processing. Improve multi-node GPU communication (UcxExchange), optimize Presto GPU query performance, and lead enhancements across Presto, Velox, and cuDF projects for efficient DataFrame and database acceleration.

Build, integrate, and stress-test full-stack applications and backend services that leverage advanced AI models. Develop production APIs, front-end features, databases, and cloud infrastructure; troubleshoot integrations; prototype rapidly and deliver high-quality code and documentation in fast-moving environments.

Looking for mid to senior level .NET/C# developers with SharePoint experience to enhance customer experience through new functionality. Candidates will document business requirements and develop application design documentation.

Seeking an experienced AngularJS and C# developer to create a data dashboarding site with reusable MVC code and templating frameworks.

The role involves developing a data dashboarding site using AngularJS, D3, and C#, focusing on creating reusable client-side MVC code with templating frameworks.

As a Software Engineer for Starlink, you will develop and support real-time software for satellites and gateways, enhancing broadband access globally.

As a Sr. Software Engineer at Bloomerang, you will lead technical direction, mentor engineers, and enhance SaaS solutions while utilizing .NET and AI tools. You will ensure scalable, maintainable applications, advocate for Agile workflows, and focus on quality outcomes in software development.

Develop and maintain C# applications using ASP.NET and Blazor, build and integrate REST APIs, design Azure Storage solutions, collaborate with offshore teams, apply AI concepts, and continuously learn new technologies. Coordinate development activities and ensure effective communication across teams.

Looking for an SQL and C# developer with 6 years of software development experience, proficient in T SQL programming and development, and strong in C#.

The role involves software development with a focus on T SQL programming and development using SQL Server and C#.

Develop and optimize ultra-low-latency, high-performance trading infrastructure in modern C++. Implement and tune order execution, market data connectivity, multi-threaded systems, and risk modules. Profile and benchmark real-time systems, collaborate with quants and traders, and maintain robust, fault-tolerant continuous trading operations.

Lead design and delivery of complex backend features for a high-scale online banking platform. Own code from design to production, modernize legacy systems, develop microservices, design APIs, implement tests, ensure secure coding, use AI-assisted tools, troubleshoot issues, and document APIs while collaborating with product, QA, and front-end teams.

Design high-performance C++ libraries for automated PCB design challenges, mentoring peers and shaping technical direction while collaborating with experts in various fields.

Develop and maintain mobile app and no-code quest editor, implement gameplay engine and server, design software architecture, and collaborate in one-week Scrum sprints using C++, Qt, QML, MySQL, and AI-assisted tools.