Top Senior C# Jobs in Denver & Boulder, CO

Develop and maintain PLM and digital engineering applications using C# and .NET. Lead software design, requirements gathering, SDLC planning, coding, testing, code reviews, and technical problem-solving. Collaborate with engineers, business analysts, architects, administrators, and business representatives to deliver application solutions. Improve development quality through automated testing, peer reviews, and development standards while mentoring and guiding team members.

Develop scalable C++ software that defines and enforces endpoint behavior across millions of managed Windows endpoints. Responsibilities include implementing features, improving platform performance, shipping production code, designing new systems, writing architecture documents, defining subsystem contracts, and collaborating with server, UI, product, and design teams. The role requires deep Windows systems and kernel-driver expertise, with preferred experience in WHQL, minifilter or WFP drivers, macOS Endpoint Security, and Linux kernel development.

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 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.

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.

Leads and develops a software engineering team while contributing hands-on to enterprise application design, coding, testing, code reviews, production support, and technical decisions. Builds scalable solutions using C#, ASP.NET, SQL Server, and modern web technologies; partners with product and business stakeholders; supports Agile delivery, CI/CD, troubleshooting, root cause analysis, and engineering best practices. The role also includes mentoring engineers, monitoring delivery and operational metrics, and driving continuous improvement.

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.

Develop and modernize enterprise applications using C#/.NET and PostgreSQL, including refactoring a Microsoft Access/VBA application. Responsibilities include writing maintainable code, participating in code reviews, testing, documentation, deployment, and collaborating with the software development team in a fully remote environment.

Develop and support AMDOTS data collection, retrieval, processing, transmission, reporting, ETL, SQL Server databases, and C++ software. Maintain Remote Monitoring Units, interfaces, networks, operating systems, software releases, documentation, disaster recovery plans, and user support. Provide data warehouse administration, technical troubleshooting, training, and site installation support in classified DoD environments, with periodic travel required.

Leads hands-on full-stack development across architecture, implementation, testing, deployment, and support. Designs secure, scalable C#/.NET and Angular applications, cloud integrations, APIs, and data solutions on AWS. Guides developers, establishes engineering standards, manages CI/CD and automated testing, troubleshoots complex issues, and drives cloud optimization, security, and technical debt reduction. Collaborates with product, architecture, DevOps, analytics, and project teams while supporting migration of on-premises applications to AWS.

Lead a development team while remaining hands-on in full-stack engineering. Design, build, test, deploy, and support secure web applications using C#/.NET, Angular, databases, and AWS. Drive cloud migrations, architecture, CI/CD automation, application security, troubleshooting, performance and cost optimization. Mentor developers, establish engineering standards, lead technical delivery, and collaborate with product, data, DevOps, and architecture teams.

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.

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 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.