Twenty is seeking a Senior Backend Engineer to work in office in our Arlington, VA office to help build the next generation of cyber technologies that protect democracies worldwide. We're looking for someone with 7+ years of experience in developing scalable applications, with deep expertise in Golang, graph databases, and cloud-native technologies, plus proven leadership experience mentoring engineers and leading technical initiatives. In this role, you'll architect and develop high-throughput systems that process real-time operational data, lead technical design decisions, mentor junior engineers, and drive engineering best practices across our backend services. You'll work with complex graph schemas, design robust GraphQL APIs, and serve as a technical leader who can evaluate engineering courses of action for new features while organizing and managing development workflows. You'll join a world-class product and engineering team that delivers mission-critical solutions for U.S. national security, working in both cloud and on-premises environments to build systems that operate at machine speed. If you're passionate about solving complex technical challenges while leading engineering teams and making a direct impact on national security, we want to talk to you.