Top C# Jobs in Denver & Boulder, CO

The Senior Software Engineer develops and maintains Sports Trading applications using .NET and SQL Server, enhancing existing functions and providing technical guidance.

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.

Lead development of software for an automated parking platform, focusing on multi-agent motion planning, fleet coordination, real-time embedded systems, simulation, integration, and deployment. Build scalable, fault-tolerant C++/ROS2 software, validate via large-scale simulation and live pilots, and collaborate across disciplines to deliver reliable production robotic systems.

Design, build, and maintain backend workflow orchestration and state management for analyzer integrations on the ECL platform. Modernize legacy .NET systems, ensure reliable event-driven operations, collaborate with integration, infrastructure, and QA teams, and preserve workflow behavior during knowledge transfer.

Lead maintenance and expansion of a flagship Windows client-server accounting product. Design, implement, test, and document features; maintain large legacy C++ codebase while developing in C#/.NET. Collaborate with cross-functional teams, gather user requirements, optimize databases, ensure code quality, and apply finance domain knowledge to deliver reliable accounting software.

Design, build, and maintain backend workflow orchestration and analyzer integrations for the ECL platform. Manage analyzer state transitions, runtime event handling, and legacy modernization; extract shared .NET libraries, collaborate with integration and QA, and support knowledge transfer.

Develop and maintain .NET-based web applications and services (REST/SOAP). Work on full-stack features using ASP.NET, WebAPI, client-side frameworks (Angular, jQuery, MVC), and SQL Server. Diagnose and optimize performance, threading, and memory usage. Implement secure, scalable, multi-threaded distributed systems, write unit/integration tests, and translate business requirements into technical designs.

Design, develop, and maintain C#/.NET web applications and services (REST/SOAP). Implement client-side features using MVC/JavaScript frameworks, optimize performance and memory/threading, perform SQL Server tuning, and write unit/integration tests. Translate business requirements into scalable, secure distributed solutions.

Design, develop, and maintain .NET/C# web applications and services (REST/SOAP). Build scalable, multi-threaded distributed systems; profile and optimize memory, threading, and performance; implement client-side features (MVC, JavaScript, Angular, Bootstrap); perform T-SQL and SQL Server performance tuning; create unit and integration tests; translate business requirements into technical designs.

Design, develop, and optimize .NET web applications and services using C#, ASP.NET, WCF/WF, Web API and REST/SOAP. Implement client-side features (Angular, jQuery, MVC), ensure security, perform DB tuning on SQL Server, write unit/integration tests, and resolve threading/memory/performance issues for scalable distributed systems.

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 Core trading systems for Linux with service-oriented architecture and multi-threaded processing. Implement async, lock-free structures and distributed systems, write unit and integration tests, optimize SQL queries, design data structures and algorithms, and work with communication protocols (SignalR, gRPC, HTTP). Use PostgreSQL, Docker, and AWS in the deployment stack.

Contribute to and optimize the performance of ClickHouse, assist with debugging, collaborate with teams, and engage with the open-source community.

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.

The Back End Software Engineer will design and build scalable services for a SaaS platform, collaborate with teams, and contribute to quality code and architecture discussions.

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

Develop a quest gameplay engine for game server and mobile apps and build a visual no-code quest editor. Collaborate in one-week Scrum sprints, design software architecture, and use C++/Qt, JavaScript/TypeScript, git, and Linux.

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, develop, implement, and analyze technical products. Conduct engineering evaluations and improve product quality. Requires a bachelor's degree and 6 years of experience.

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.

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.

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

Lead a development team focused on data processing and statistical analysis, ensuring high-quality software development and complex report packaging for clients.

The C# Developer, Analyst will implement and customize software, troubleshoot issues, and engage with clients, balancing coding and business interactions.

Seeking a C# / MVC Developer to convert a VB.NET site to C# / MVC. Responsibilities include full stack .NET development, SQL development, and testing.