Principal Software Engineer

Job Description: Building trusted markets — powered by our people   At Cboe Global Markets, we inspire our people to solve complex challenges together because what we do matters. We provide the financial infrastructure that powers the global economy. As a leading provider of market infrastructure and tradable products, Cboe delivers cutting-edge trading, clearing and investment solutions to market participants around the world.  We’re building meaningful ways to support professional and personal development while strengthening the trust we’ve earned as a global market leader. Our teams are empowered to share ideas, actively pursue them and bring on a challenge. As champions of internal mobility and access to opportunity, we encourage our people to “go for it” and equip our managers with the training to coach their teams to the next level. We strive to provide employees a safe space to network, share ideas and create opportunities.   To support strong partnership and team connection, this role follows a four day in office work model. Location Overview Cboe HQ is located in the historic Old Post Office district, it’s a landmark that blends classic architecture with modern amenities. The building features expansive spaces with high ceilings and large windows, offering an abundance of natural light and panoramic views of the city skyline and the Chicago River. With its prime location in the heart of downtown, the OPO Building provides easy access to major transportation hubs, including Union Station and multiple CTA lines, making it convenient for commuters. The building is home to a variety of amenities, including restaurants, a fitness center, and collaborative workspaces, creating a vibrant and dynamic work environment in one of Chicago's most iconic areas. Role Overview Cboe’s Data Vantage division — the team behind Silexx, LiveVol, and DataShop — is looking for a Principal Software Engineer who builds across the entire stack and owns the integration and end-to-end testing that keeps our platforms working together. This is a hands-on principal role for a seasoned full-stack engineer who is an expert in modern ReactJS front-end development, fluent in C#/.NET back-end services, and comfortable navigating a WPF desktop client. You will design and implement real-time web and desktop applications and scalable back-end systems for financial analytics, execution, and risk-management platforms — and you will define how we validate them across products. We expect you to work fluently with AI coding assistants such as Claude throughout the software development lifecycle, using them to accelerate delivery, generate and maintain test suites, review code, and raise quality across the team. The ideal candidate has spent years engineering complex real-time UIs, has a deep understanding of web streaming technologies and RESTful/gRPC transport protocols, and is energized by breaking down product silos to deliver integrated, well-tested software across the platform. Your responsibilities will be: Serve as the subject-matter expert for integration and end-to-end testing, working across the Silexx, LiveVol, and DataShop teams to define and refine how we validate workflows that span the front-end, APIs, and back-end services. Lead the design, architecture, and implementation of modern full-stack applications using ReactJS front-ends and C#/.NET back-end services. Build and maintain automated integration, contract, and end-to-end test suites that exercise REST, gRPC, and real-time streaming interfaces across products, and wire them into CI/CD pipelines as release gates. Leverage AI coding assistants such as Claude across the SDLC — for test generation, code review, refactoring, and agentic automation — and help establish team practices and guardrails for AI-augmented development. Collaborate with product management and cross-functional teams across products to understand requirements and deliver integrated, high-quality solutions. Implement secure server communications and authentication/authorization using RESTful and streaming protocols, OpenID Connect, and OAuth 2.0. Drive technical decisions, provide architectural direction for growth into new asset classes and products, and mentor engineers across teams. Diagnose and resolve complex, cross-product technical problems spanning the UI, API, and back-end layers. The ideal candidate has Bachelor’s degree in Computer Science, Software Engineering, or a related STEM field. 10+ years of hands-on experience in professional full-stack development, including modern web technologies and back-end services. Demonstrated experience designing and leading integration and end-to-end test strategy for complex, multi-component systems. Strong OOP skills, experience with design patterns, and a solid grounding in computer science fundamentals. Experience mentoring engineers and providing technical leadership across teams. Hands-on experience using AI coding assistants (e.g., Claude) in a professional development workflow. Additional Skills & Requirements Development: Expertise in ReactJS, React Hooks, MobX or Redux, and component-based architecture. Strong proficiency in HTML5, CSS3, JavaScript (ES6+), and TypeScript. Advanced experience with C#/.NET and ASP.NET for building robust back-end services. Experience with front-end build tools such as Webpack, Babel, and NPM. Proficiency in building and consuming RESTful APIs, gRPC, WebSockets, and other real-time communication methods. Expertise in throughput optimization techniques, serialization (MessagePack, Protobuf), and compression methods. Experience with microservices architecture. Working knowledge of WPF desktop clients sufficient to build against, integrate with, and test them (e.g., the Silexx OEMS). Strong understanding of data structures and algorithms, profiling, and performance optimization. Testing & Quality: Expertise designing and implementing integration, contra