Senior Frontend Software Engineer

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 be a high-output engineer building mission-critical operator experiences — implementing complex, high-performance interfaces that visualize real-time cyber operation data with speed and precision. You'll contribute meaningfully to frontend architecture and design decisions, own significant features end-to-end, and raise the quality of the codebase around you. You'll work closely with other frontend engineers and cross-functional partners across backend, product, design, and operations to ship capabilities that must work reliably in both cloud and on-premises environments.

Lead and develop a cross-disciplinary team of engineers spanning frontend, backend, data, and infrastructure.

Own the technical roadmap for the product; partner with the Product Manager on the product roadmap.

Build the data pipelines that ingest target-technology intelligence from an upstream target-intelligence system and capability usage, quality, and failure data from an operational performance and feedback system.

Lead development of a gap-analysis engine that identifies unmet operational demand without relying on manually written requirements documents.

Translate gap analysis into high-confidence, appropriately obfuscated demand signals that help vendors decide what to build.

Build automated matching between verified capabilities and observed operational gaps.

Define and ship buyer-facing metrics such as probability of success, utilization likelihood, vendor reliability, and cost-to-effect.

Establish evaluation and feedback systems that improve recommendations using actual deployment and performance outcomes.

Design privacy, anonymity, KYC, access-control, and OPSEC protections into the product from the start.

Guide architecture and technical decisions to keep data products, marketplace workflows, and integrations coherent, secure, explainable, and scalable.

Establish and enforce engineering quality standards: design reviews, testing discipline, documentation, observability, data-quality controls, and secure development practices.

Coordinate dependencies with an upstream target-intelligence system, an operational performance and feedback system, Product, and other internal consumers; communicate clearly on timelines, risks, assumptions, and tradeoffs.

Hire, onboard, and develop engineers; give direct feedback, build growth plans, and cultivate technical leadership within the team.

Run structured hiring end-to-end: define the bar, build the interview process, run rigorous debriefs, and close strong candidates.

Occasionally contribute hands-on—code review, prototyping, implementation, data investigation, or debugging—when it unblocks the team or accelerates delivery.

You care about building software that has real-world impact in high-stakes environments.

You write clean, precise, and well-tested code and hold yourself to that standard without being asked.

You think carefully about performance, reliability, accessibility, and maintainability as you build.

You make sound tradeoffs under constraints and communicate them clearly to teammates.

You're drawn to complex data problems and enjoy turning them into interfaces that help users act quickly.

You take ownership of your work end-to-end — from design review to production — and take pride in delivering on your commitments.

You default to secure engineering practices and treat trust, safety, and correctness as non-negotiable.

You have experience with complex data visualization (e.g., D3.js, Chart.js, or similar).

You have exposure to graph databases or graph query patterns (e.g., Neo4j).

You have experience with real-time streaming data and live system visualization.

You have worked in defense, security, or other mission-critical domains.

You have built UI experiences that surface AI/ML outputs in operational workflows.

You have experience contributing to component libraries or design systems (e.g., Storybook).

Benefits What's on the table:

Health. Medical, dental, and vision plan options. Life / AD&D, disability coverage options.

Family. Paid parental leave for eligible full-time employees. 12 weeks for birthing parents, 4 for non-birthing parents, 6 weeks for adoptive, foster, or intended parents through surrogacy.

Vacation. Paid holidays and flexible PTO. Take what you need.

Retirement. 401(k) with pre-tax and Roth options. HSA/FSA options, dependent care FSA.

Benefits vary by location, role, and eligibility. Full plan details provided during the interview and offer process.

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

Due to U.S. government contract and security requirements, this role is limited to U.S. citizens. Some positions may also require eligibility to obtain and maintain a U.S. Government security clearance. Any active 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, consistent with applicable law.

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