Cboe Data Vantage is seeking a highly skilled Principal Software Engineer to lead the re-architecture and modernization of our real-time Portfolio Risk Analytics system. This is a critical role for an experienced engineer with a strong background in C#/.NET back-end development and expertise in the equity and index options industry. The system processes real-time market data, reference data, and positions updates to generate risk metrics and projected scenarios, powering critical decision-making tools. As a Principal Engineer, you will play a key role in rearchitecting the existing system to make it more scalable, supportable, and performant, while also supporting and optimizing the current system during the transition. You will focus on building robust back-end systems that power modern web-based applications (though you will not be required to write web code directly). This role also involves technical leadership, mentorship, and collaboration with cross-functional teams to deliver enterprise-grade solutions.