Full Stack Engineer

Twenty

Twenty

Software Engineering
Washington, DC, USA
Posted on Nov 20, 2025

Location

Washington DC

Employment Type

Full time

Location Type

On-site

Department

Engineering

Twenty is seeking a Full Stack 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 4+ years of experience in developing scalable applications, particularly using React.js, Golang, graph databases, and cloud-native technologies. In this role, you'll design and develop high-throughput systems that process real-time operational data, work with complex graph schemas, and create GraphQL APIs that form the backbone of our cyber and electromagnetic capabilities. 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 Company

At 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 Details

  • Design and implement scalable full-stack solutions across our React frontend and Go backend services that enhance cyber operators' decision-making and response capabilities

  • Develop high-performance, real-time user interfaces that process and visualize complex cyber operation data streams

  • Build and optimize GraphQL APIs that enable rapid data access and manipulation

  • Implement efficient data models and queries using Neo4j to support complex relationship mapping

  • Design and maintain event-driven architectures using NATS for real-time communication between system components

  • Create and maintain automated testing suites to ensure system integrity and performance

  • Design and implement microservices architectures deployed on Google Cloud Platform

  • Develop and maintain CI/CD pipelines that enable rapid, secure deployment of new capabilities

  • Work closely with cyber operations experts to understand and implement features that enhance operator efficiency

  • Research and evaluate new technologies that could enhance our cyber operations capabilities

Qualifications

Technical Skills & Experience

  • 4+ years of professional software development experience with full-stack applications

  • Strong proficiency in React.js and modern JavaScript/TypeScript development

  • Experience with Go (Golang) backend development

  • Proven experience with GraphQL API design and implementation

  • Working knowledge of event-driven architectures and message queues

  • Experience with graph databases (Neo4j or similar)

  • Proficiency with cloud platforms, preferably Google Cloud Platform

  • Experience with containerization and microservices architectures

  • Strong understanding of security best practices and secure coding principles

Education

  • Bachelor's degree in Computer Science, Software Engineering, or related fields, or equivalent practical experience

Security Requirements

  • Must be eligible to obtain a U.S. Government security clearance

Distinguishing Qualifications

  • Track record of delivering complex technical solutions in defense or security contexts

  • Experience with AI/ML integration in operational systems

  • Background in developing tools for cyber operators or security analysts

  • Experience with large-scale data processing and analysis

Additional Skills

  • Experience with Agile development methodologies

  • System architecture and design experience

  • Performance optimization and scalability experience

  • Open-source contributions or personal projects demonstrating relevant skills