Top C# Jobs in Boston, MA

Design, develop, and field high-performance Ground Control Station and C2 software using C++/Qt/QML and QGroundControl. Lead architecture and technical direction, mentor engineers, define APIs/ICDs, debug integration/latency issues, support field tests, implement post-mission debrief tools, and ensure interoperability with C2 standards.

Build and optimize high-performance C/C++ and Rust server applications and feed handlers for market data. Implement parsers, petabyte-scale processing tools, and low-latency, high-throughput optimizations. Collaborate on build/deploy/CI, monitoring, and ensure reliable feature rollouts.

Lead the technical direction for integrating algorithms on the Prism Mapping platform, focusing on real-time signal pipelines and optimization strategies. Collaborate with teams to ensure robust clinical performance and timely delivery of new capabilities.

As a Senior Software Engineer, you'll develop signals and algorithm interfaces, collaborate with developers, optimize algorithms, and mentor engineers in a regulated environment.

The C# Developer will work on projects utilizing C#, WPF, and BLE development with an emphasis on medical process compliance.

Develop and support software tools for chip design and verification, optimize workflows, work collaboratively to create high-performance software.

As a Senior Software Engineer - C++ GPU Performance, you will optimize GPU algorithms, monitor performance metrics, and influence design decisions for self-driving technology.

The role involves optimizing GPU-based algorithms, developing benchmarking frameworks, analyzing performance metrics, and facilitating efficient code development for autonomous vehicle systems.

Design, develop, and maintain scalable full-stack enterprise applications using C#, .NET, ASP.NET, and Microsoft Azure. Build RESTful APIs and cloud services, modernize existing systems, troubleshoot production issues, and collaborate with technical and business stakeholders. Participate in architecture, code reviews, testing, deployment, and production support while following secure and maintainable development practices.

Evaluate AI coding-agent interactions for usefulness, correctness, engineering judgment, reasoning quality, and developer trust. Provide clear, opinionated feedback, distinguish response-quality levels, and help define standards for excellent interactions with tools such as OpenAI Codex, Claude Code, and Cursor. This contract role requires staff- or principal-level software engineering experience and familiarity with modern AI-assisted development workflows.

Design, build, and maintain scalable full-stack web applications using React, Python, Node.js, and C#. Develop cloud-native AWS solutions with event-driven and serverless architectures, manage relational and NoSQL data stores, write automated tests, maintain infrastructure as code, and contribute to CI/CD pipelines. Collaborate with cross-functional engineering teams on architecture, security, performance, and end-to-end feature delivery in an agile environment.

Develop and maintain end-to-end applications using Python, Node.js, C#, and React. Build scalable backend services, frontend features, APIs, cloud-native AWS solutions, automated tests, infrastructure as code, and CI/CD pipelines. Collaborate with cross-functional engineering teams in an agile, remote environment while contributing to architecture and reliable product delivery for US clients.

The C++ Software Engineer will develop, enhance, and maintain financial software at oneZero, focusing on performance and reliability. Responsibilities include collaborating with teams and resolving production issues.

Develop and maintain the Java client library and high-performance C/C++ server applications. Implement message parsers and feed handlers, optimize for extreme throughput and low latency, build tools for petabyte-scale processing, collaborate on build/deploy/CI practices, monitor uptime, and support smooth feature rollouts.

Implement and maintain the C# client library and high-performance C++ server applications. Build message parsers and feed handlers, optimize for millions of messages/second and nanosecond latency, develop petabyte-scale data tools, collaborate on build/deploy/CI/CD, monitoring, and ensure reliable feature rollouts.

The C# / .NET Developer will design and maintain middleware applications, build Shopify integrations, and support a mobile app backend in a remote work environment.

Design and evaluate performance engineering tasks for AI training/evaluation. Optimize runtime, compilers, memory, CPU/GPU and concurrency. Produce documented solutions, evaluate AI-generated code, and build evaluation frameworks and scoring rubrics while collaborating with researchers and SMEs.

Develop user interface components for ArcGIS Pro using C# and WPF, work in an agile team, and design software solutions for raster and imagery processing.

PrivateID seeks a Principal C++ Engineer with at least 10 years of experience to lead complex systems and scale their platform in a remote-first environment.

Build and maintain scalable, cloud-native APIs using .NET. Enhance core platform components, lead architecture and testing discussions, optimize telemetry and performance, collaborate cross-functionally, conduct code reviews, and mentor team members.

You will develop and maintain components of the LLVM based toolchain, collaborating with the community while ensuring platform-specific optimizations and tests.

Remote backend C# developer to build and optimize a high-load spot-exchange matching engine. Improve performance and API throughput, implement business features, write unit and integration tests, work with .NET Core and PostgreSQL on AWS, and apply multithreading, async, and distributed systems concepts.

Develop and maintain .NET/SharePoint applications using C#, ASP.NET, WCF/REST services and .NET MVC. Work with front-end technologies (HTML5, CSS, jQuery, Kendo, Bootstrap), T-SQL/SQL Server tuning, source control (VSS/TFS), and apply design patterns. Ensure performance, security, scalability and collaborate in a global delivery environment.

Design and implement ultra-low-latency C++ trading gateway components, build market access interfaces (FIX/OUCH), optimize NUMA-aware multithreaded systems, employ userspace networking, lock-free techniques, and compiler/cache optimizations, and lead related projects.

Design and implement low-latency C++ gateway infrastructure for market access. Build and optimize order-entry interfaces (e.g., FIX, OUCH), apply NUMA-aware multithreading, userspace networking, compiler/cache optimizations, and lock-free techniques. Contribute to architecture and performance tuning using strong algorithms, data structures, and modern C++ best practices.