Frontend Developer

Twenty is seeking a mid-level Frontend Engineer for an in-office position in its Arlington, VA office to help build the next generation of cyber technologies that protect democracies worldwide. We're looking for someone with 6+ years of experience in developing scalable frontend applications, with deep expertise in React.js, TypeScript, and modern web technologies, plus working knowledge of backend systems including Golang, graph databases, and cloud-native platforms. In this role, you'll design and develop sophisticated, high-performance user interfaces that visualize complex cyber operation data in real-time, creating intuitive dashboards and interactive experiences that help operators quickly understand and act on critical information from our graph-based cyber and electromagnetic systems. 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 making a direct impact on national security, we want to talk to you. About the CompanyAt Twenty, we're taking on one of the most critical challenges of our time: ensuring democracies prevail in the digital age. We develop revolutionary technologies that operate at the intersection of cyber and electromagnetic domains, where the speed and complexity of operations exceeds human cognition. Our team doesn't just solve problems – we deliver game-changing outcomes that directly improve national security. We're pragmatic optimists who know that while our mission of defending America and its allies is challenging, we can succeed. Role DetailsDesign and implement scalable full-stack solutions across our React frontend and Go backend services that enhance cyber operators' decision-making and response capabilitiesDevelop high-performance, real-time user interfaces that process and visualize complex cyber operation data streamsCreate interactive data visualizations using D3.js, Chart.js, or similar librariesImplement efficient data models and queries using graph databases to support complex relationship mappingImplement responsive, accessible user interfaces that work across devices and screen sizesCreate and maintain automated testing suites to ensure system integrity and performanceWork with backend APIs and contribute to Go services when neededWork closely with cyber operations experts to understand and implement features that enhance operator efficiencyResearch and evaluate new technologies that could enhance our cyber operations capabilitiesQualificationsTechnical Skills & Experience6+ years of professional software development experience with full-stack applicationsExpert knowledge of modern JavaScript/TypeScript, HTML5, and CSS3Experience with frontend build tools, bundlers, and development workflowsProven experience with GraphQL API design and implementationKnowledge of web accessibility standards (WCAG) and performance optimizationExperience with frontend testing frameworks (Jest, React Testing Library, Cypress)Experience with graph databases (Neo4j or similar)Proficiency with cloud platforms, preferably AWSUnderstanding of UX/UI principles and collaboration with design teamsStrong understanding of security best practices and secure coding principlesEducationBachelor's degree in Computer Science, Software Engineering, or related fields, or equivalent practical experienceSecurity RequirementsMust be eligible to obtain and maintain a U. S. Government security clearanceDistinguishing QualificationsTrack record of delivering complex technical solutions in defense or security contextsExperience with AI/ML integration in operational systemsBackground in developing tools for cyber operators or security analystsExperience with large-scale data processing and analysisAdditional SkillsExperience with Agile development methodologiesSystem architecture and design experiencePerformance optimization and scalability experienceOpen-source contributions or personal projects demonstrating relevant skills Apply to this Job