Senior Frontend Engineer – Real-Time Cyber Ops UI

Twenty; Arlington (VA); On-site; USD 140,000 - 180,000; Full time

Benefits offered by this job

Health benefits

Parental leave

Paid holidays

401(k) plan

Job summary

Twenty Technologies is seeking a senior frontend engineer who will build mission-critical operator interfaces in React/TypeScript. You will own features end-to-end, work with cross-functional teams, and ship reliable interfaces for real-time cyber operation data in cloud and on-prem environments.

The role emphasizes performance, testing, and secure engineering practices, with collaboration across frontend, backend, product, design, and operations to deliver high-quality user experiences on-site

Qualifications

• 5–8 years of frontend software development experience.
• Strong production-tested React.js and TypeScript skills.
• Proficient in modern web fundamentals (JavaScript/TypeScript, HTML, CSS).
• Experience shipping features for performance at scale and profiling.
• Hands-on testing with Vitest/RTL/Playwright or Cypress.
• Experience with Redux, Zustand, or React Query for state management.
• Modern build tooling and CI/CD pipelines (Vite/Webpack).
• Collaborates with product and design to deliver high-quality UX.
• Strong Git skills, branching, code reviews, and CI integration.
• Bachelor’s degree in CS/Engineering (or equivalent).

Responsibilities

• Build sophisticated React/TypeScript features and components at scale.
• Implement real-time UI experiences for complex data with speed and clarity.
• Contribute to frontend architecture and design decisions with teammates.
• Build and maintain interactive visualization components (graphs, timelines, streaming views).
• Write and maintain automated tests across unit, integration, and end-to-end layers.
• Participate in code reviews to raise quality and share feedback.
• Identify and address performance issues, debt, and reliability gaps.
• Collaborate with design, product, backend, and operations on features.
• Support engineers through pairing and constructive feedback.

Skills

React.js

TypeScript

JavaScript

HTML/CSS

Automated testing

Redux

Git

CI/CD

Education

Bachelor's degree in CS/Engineering

Tools

Vitest

React Testing Library

Playwright

Cypress

Job description

Twenty Technologies is seeking a senior frontend engineer who will build mission-critical operator interfaces in React/TypeScript. You will own features end-to-end, work with cross-functional teams, and ship reliable interfaces for real-time cyber operation data in cloud and on-prem environments.

The role emphasizes performance, testing, and secure engineering practices, with collaboration across frontend, backend, product, design, and operations to deliver high-quality user experiences on-site