Senior Frontend Engineer leading product vision at HumanSignal in AI data platform. Building accessible UX in React/TypeScript, collaborating with product and design.
Responsibilities
Build and maintain frontend components and views for labeling, review, and evaluation workflows with performance, accessibility, and scalability in mind.
Own outcomes, not tasks: refine scope, suggest trade-offs, propose simpler approaches, and land increments that deliver value fast.
Partner with Product & Design from discovery to delivery: clarify user jobs, write lightweight RFCs/PRDs, and shape scope and milestones.
Prototype to de-risk UX; use flags/gradual rollouts; gather feedback from users/support and iterate after releases.
Raise the bar on FE standards: state management, testing, error boundaries, a11y, i18n, and developer ergonomics.
Partner with Support to investigate production issues, reduce UX papercuts, and turn learnings into fixes.
Engage with our open-source community (issues, discussions) to understand real-world needs and improve developer experience.
Participate in architecture discussions and code reviews; mentor teammates and improve patterns across the codebase.
Requirements
Senior-level experience shipping production React/TypeScript apps (HTML/CSS mastery; ES6+; a11y).
Strong product sense: you’ve made scope/trade-off decisions and iterated based on real-world usage and feedback.
Fluency with modern FE tooling (e.g., Vite/Webpack, Jest/Cypress) and state-management patterns.
Comfort collaborating with APIs and occasionally touching backend code (Django/REST familiarity is a plus).
Excellent communication at a Senior IC level — you write clear RFCs/PRDs, give actionable reviews, and present trade-offs well.
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