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Staff / Principal Frontend Software Engineer

Twenty · Arlington, VA · On-site

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About Twenty

The #1 Open Source CRM for modern teams. Modular, scalable, and built to fit your business. Backed by Y Combinator.

About the role

Architect and build sophisticated React/TypeScript applications that operate smoothly at scale. Design real-time UI experiences for complex cyber operation data, optimizing for speed and clarity.

What they're looking for

  • You care about building software that has real-world impact in high-stakes environments
  • You lead with high standards and high support—clear feedback, strong mentorship, calm execution
  • You think in systems: performance, reliability, accessibility, and maintainability are first-class concerns
  • You make good tradeoffs under constraints and can explain them crisply to technical and non-technical partners
  • You enjoy turning complex data into intuitive workflows that help users make decisions quickly
  • You’re comfortable owning ambiguous problems end-to-end and driving them to measurable outcomes
More about this role

America is under sustained cyber attack. Our adversaries infiltrate our networks, steal our IP, and degrade the digital infrastructure that modern life runs on. They’ve learned—correctly—that those attacks rarely produce consequences.

Twenty was founded to change that, by making our adversaries think twice before they attack us. Our vision is American and allied primacy in cyberspace—a future where they cannot contest us, deterrence is assured, and the free world remains secure.

Founded in 2024, Twenty Technologies ( www.twenty.io ) industrializes offensive cyber operations for the U.S. and its allies. Headquartered in Arlington, Virginia, Twenty has raised $168M from Khosla Ventures, Accel, Caffeinated Capital, Friends & Family Capital, Point72 Ventures, General Catalyst, and In-Q-Tel.

Mission | On Site | Full Time | U.S. Citizenship Required / No Active Clearance Required

You'll own the frontend architecture for mission-critical operator experiences—building high-performance interfaces that visualize complex cyber operation data in real time. You'll lead technical direction for UI systems, set the bar for engineering quality, and mentor engineers to move faster with confidence....

Read the full posting on Twenty's site ↗

Engineering

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