Top Senior C# Jobs in Denver & Boulder, CO

Design and develop scalable C++ software for endpoint state and control across Windows, macOS, and potentially Linux. Build reliable, multi-process systems that enforce endpoint behavior, manage local state, support IPC, and operate across millions of devices. Responsibilities include implementing features, improving platform performance, writing design documents, defining architecture and IPC contracts, and making technical decisions in an evolving, sparsely documented environment.

Build and scale low-latency ad-serving software handling billions of daily auctions. Responsibilities include developing data- and model-driven features, optimizing algorithms and architectures, reducing cloud costs, extending observability, supporting distributed infrastructure, participating in on-call rotations, and documenting systems and incident procedures.

Develop and maintain a cross-platform C++ endpoint agent that detects, installs, validates, and rolls back operating system and third-party software patches. Responsibilities include code review, mentoring engineers, improving development processes, collaborating across teams, and translating product needs into technical designs. The role requires system-level development across Windows, macOS, and Linux using modern C++, gRPC, Protocol Buffers, SQLite, and CMake.

Develop and maintain sports trading and tools applications and platforms using .NET, C#, and SQL Server. Build scalable, low-latency, highly available software handling high-volume real-time data. Support existing 24/7 trading systems, perform root-cause analysis, collaborate with product owners and testing teams, contribute to solution proposals and estimates, and mentor technical team members. The role will also expand into Golang, React, and Google Cloud Platform.

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.

Design, develop, test, and optimize high-fidelity C++ emulators for SPARC-based flight computers and mission-critical space flight hardware. Integrate emulation capabilities into flight and ground software workflows, meet demanding performance requirements, document and test solutions, and contribute to CI/CD pipelines. The role requires collaboration with architects, engineers, and customers in a mission-focused environment, with potential DoD clearance eligibility.

Design, implement, test, and modernize backend services and integrations (TypeScript/Node.js and C++). Lead large projects, write technical specifications and API contracts, enforce coding standards, coach engineers, and drive legacy-to-modern migrations within online banking and core systems.

Lead end-to-end development of secure, scalable web applications and data solutions supporting clinical trial operations. Design frontend and backend components using C#/.NET, Angular, AWS, and relational or non-relational databases. Guide architecture, testing, deployment, CI/CD, security, cloud optimization, and regulatory compliance. Mentor developers, oversee technical delivery, troubleshoot complex issues, and lead migration and modernization of on-premises applications to AWS.

Lead the architecture, design, and implementation of core MarkLogic database features using C++. Build scalable, fault-tolerant distributed systems; optimize performance; debug complex server-side issues; and mentor engineers. Collaborate with product, development, QA, and documentation teams to deliver secure, high-quality database capabilities involving search, security, language runtimes, JavaScript integration, scalability, and reliability.

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

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

The Sr. C# Developer will work in an Agile/Scrum environment focusing on .NET development, rich UI web applications, and commercial software.

Seeking a C# Engineer, Architect to join a team, focusing on development and providing a technology roadmap. Requires strong architecture skills.

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.

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.

Design, implement, and optimize high-performance C++ software for remote sensor data processing (OPIR) on Linux. Develop image analysis, detection, and tracking algorithms; improve scalability and reliability; participate in code reviews, integration, testing, and Agile development; collaborate with algorithms, systems, and integration teams.

Develop, optimize, and maintain high-throughput C++ software for processing OPIR and remote sensing data on Linux. Lead small teams, implement algorithms for detection and tracking, improve performance and scalability, support integration/testing, participate in code reviews, mentor teammates, and work directly with customers through the software development cycle in an Agile environment.

Develop and optimize high-throughput C++ algorithms for remote sensor data exploitation (image analysis, detection, tracking). Prototype, integrate, and test software within government frameworks as part of an Agile team. Work full-time in-person in Boulder, CO and obtain/maintain DoD security clearance.

Develop, optimize, and integrate high-throughput C++ algorithms and multi-object tracking software for counter-UAS and remote sensing systems. Work in an Agile small-team environment to prototype, test, and deliver low-latency processing solutions within government frameworks.

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 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.