Twenty is seeking a Principal Backend Engineer to work in our Arlington, VA office to architect and lead the development of revolutionary cyber technologies that protect democracies worldwide. We're looking for someone with 12+ years of experience in developing large-scale distributed systems, with mastery-level expertise in Golang, graph databases, and cloud-native technologies, plus a proven track record of driving technical strategy and leading major architectural initiatives across organizations. In this role, you'll serve as the principal technical authority for our backend systems, defining the technical vision and architecture for systems that process real-time cyber operation data at machine speed, lead cross-functional technical initiatives, mentor senior engineers, and drive innovation in how we apply AI, graph databases, and distributed systems to national security challenges. 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 the cutting edge of cyber warfare capabilities. If you're passionate about solving the most complex technical challenges while shaping engineering culture and making a direct impact on national security, we want to talk to you. About the Company At Twenty, we're taking on one of the most critical challenges of our time: defending democracies in the digital age. We develop revolutionary technologies that operate at the intersection of cyber and electromagnetic domains, where the speed of operations exceeds human sensing and complexity transcends conventional boundaries. Our team doesn't just solve problems – we deliver game-changing outcomes that directly impact national security. We're pragmatic optimists who understand that while our mission of protecting America and its allies is challenging, success is possible.