Full Stack Engineer

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 the 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.

You'll build full-stack systems that turn real-time operational data into fast, usable capabilities for cyber and electromagnetic missions. This role spans a React/TypeScript frontend and Go services that power high-throughput workflows, complex data models, and GraphQL APIs. You'll partner closely with product, engineering, and mission experts to ship software that performs at machine speed in both cloud and on-premises environments.

• You care about building mission-critical software that protects democracies and supports U.S. national security.

• You're energized by complex systems: real-time data, performance constraints, and hard engineering tradeoffs.

• You write software that's reliable under pressure—tests, instrumentation, and operational rigor are part of how you work.

• You move quickly without being sloppy: you can iterate fast and still ship production-grade systems.

• You communicate clearly with technical and non-technical partners, and you like tight feedback loops.

• You take ownership end-to-end, from design through rollout, monitoring, and improvement.

• Design and ship scalable full-stack features across React frontends and Go backend services.

• Build high-performance UIs that ingest and visualize real-time operational data streams.

• Develop and optimize GraphQL APIs for fast, flexible access to mission data.

• Model complex relationships and implement efficient queries for mission-critical datasets.

• Design event-driven services and workflows for low-latency, real-time communication between components.

• Build and maintain automated tests that protect correctness, performance, and reliability.

• Contribute to microservices deployed across cloud and on-premises environments.

• Improve delivery velocity with pragmatic CI/CD and release practices.

• Partner with operators and domain experts to translate real-world workflows into usable software.

• You have 4+ years of professional experience building scalable full-stack applications.

• You have strong React experience and proficiency in modern JavaScript/TypeScript.

• You have production experience building backend services in Go (Golang).

• You have designed and implemented GraphQL APIs in real systems.

• You have experience with event-driven architectures and message-based systems.

• You have experience deploying and operating services in a cloud environment.

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

• You have experience with graph databases (Neo4j or similar) and complex relationship modeling.

• You have experience delivering software in defense, intelligence, or security contexts.

• You've built tools for operators, analysts, or security teams handling time-sensitive workflows.

• You have experience with large-scale data processing and performance tuning for high-throughput systems.

• You've integrated AI/ML capabilities into production, operational systems.

• You've contributed to open-source projects or shipped high-quality personal projects.

• React, TypeScript, GraphQL

• Go (Golang), microservices, containerized deployments

• Neo4j and complex graph schemas

• NATS and event-driven architectures

• Google Cloud Platform, CI/CD pipelines

• Cloud and on-premises deployments

Some positions may require eligibility to obtain a U.S. Government security clearance. This role may involve work in a controlled environment.

If this role sounds like you, apply and share with us your interest.

Some positions may require eligibility to obtain a U.S. Government security clearance. Any clearance requirement will be listed in the role description.

Twenty is an equal opportunity employer. We consider all qualified applicants without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, veteran status, disability, or any other protected status.

If you need a reasonable accommodation during the hiring process, let us know and we will work with you.