Senior/Staff React Frontend Engineer

Senior/Staff React Frontend Engineer Why Nuclearn.ai Nuclearn.ai builds AI-powered software for the nuclear and utility industries—tools that keep critical infrastructure reliable, efficient, and safe. Our software integrates AI-driven workflow, documentation, and research automation, and is already used at 60+ nuclear reactors across North America. You'll ship production code operators and engineers rely on every day. We're growing quickly, expanding our team and our Phoenix HQ. The work is consequential: what you build helps real plants run safer and smarter. Eligibility: U.S. citizenship or permanent residency (green card) is required due to DOE export compliance. What You’ll Do Architect scalable frontend systems that handle complex data workflows and real-time updatesBuild sophisticated data visualizations that make ML model outputs interpretable and actionableDesign and implement component libraries that balance flexibility with consistencyOptimize performance for data-heavy applications while maintaining excellent UXCollaborate deeply with backend engineers, data scientists, and domain experts to translate complex requirements into elegant interfacesEstablish frontend standards and drive technical decisions across the engineering teamMentor engineers and elevate the entire team's frontend capabilitiesShip features end-to-end from concept to production, owning the quality and user experience Examples of problems you might own in your first 90 days Building real-time monitoring interfaces used in mission-critical nuclear operationsDesigning complex, high-dimensional ML visualization components that make automated insights actionableEstablishing a robust frontend architecture and shared component system that scales with the engineering team What Makes You a Great Fit Technical Excellence 7+ years building production web applications with deep expertise in React and modern JavaScript/TypeScriptMastery of state management patterns (Redux, Zustand, React Query, Context, etc.)Strong computer science fundamentals, including performance optimization and debugging complex systemsExperience architecting large-scale applications designed for long-term maintainabilityProficiency with modern tooling (Vite/Webpack, testing frameworks, CI/CD) Product Mindset You think beyond implementation—asking why and should we as often as howExperience collaborating with designers, or designing interfaces yourself when neededTrack record of creating intuitive, delightful user experiencesComfortable making pragmatic tradeoffs in ambiguous and fast-changing environments Communication & Leadership Ability to explain complex technical decisions to non-technical stakeholderExperience mentoring engineers and performing thoughtful code reviewsSkilled at driving consensus and influencing technical directionThrive in a collaborative, fast-paced startup environment Self-Directed Impact Able to contribute independently within 6 weeksHigh degree of ownership and ability to drive problems end-to-endProactively identifies improvements and executes on them Nice To Have (not Required) Experience with data visualization libraries (D3.js, Recharts, Plotly, etc.)Background in complex domains (scientific, industrial, financial, healthcare)Contributions to open source or technical writingExperience with WebGL, Canvas, or high-performance graphicsKnowledge of accessibility (WCAG) and building inclusive interfacesFull-stack capabilities or strong understanding of backend systemsPrior startup experience or leading engineering initiatives Impact You’ll Have (near-term roadmap) Improve the reliability and usability of interfaces used daily at nuclear power plantsShape the foundation of our shared component library & frontend patternsLead development of new visualization systems for ML-driven analysis and operator workflows Work Model & Schedule Full-time, salariedMon–Fri hybrid (Wed remote); expectation is ≥80% in-office (Phoenix HQ) How We Hire (fast, respectful, practical) 20-min intro with the founder/hiring manager to trade context and assess mutual fitPractical work sample (60–90 min; a real task in our stack)Team meet + peer programming (system design + collaboration) We aim to move from first chat to decision quickly.