Senior Frontend Engineer

Role Overview

JuiceX is hiring a Senior Frontend Engineer to build and own the web trading interface for its Exchange. The UI is where users place trades, monitor positions, and react to live market data in real time—so performance, correctness, and reliability directly impact financial outcomes.

Responsibilities

• Own end-to-end frontend experience, including real-time state, performance, and testing.
• Build and maintain a streaming state architecture for a reliable live UI:
  • WebSocket connections
  • reconnection handling
  • backpressure
  • stale data detection
• Deliver real-time trading workflows, including order entry and position monitoring.
• Establish and evolve testing across layers (unit, integration, end-to-end), including Playwright for critical trading flows.
• Maintain clean module boundaries in a large monorepo with shared packages.
• Build and evolve the design system/component library, ensuring Figma-to-code parity and staying consistent as it grows.
• Optimize performance and responsiveness on dense, data-heavy screens.
• Ensure accessibility (WCAG) across the trading interface.
• Partner with Product, Design, Market Operations, and platform/engineering teams to translate market data and workflows into accurate UI.

Requirements

• 5+ years building and maintaining production web applications with senior-level ownership.
• Deep expertise in TypeScript and modern React:
  • hooks
  • concurrent rendering
  • Suspense
  • React 19 / Strict Mode practices
• Proven experience shipping real-time, data-intensive UIs (WebSockets/streaming state, reconnection, stale data handling, backpressure).
• Strong testing mindset across unit, integration, and end-to-end.
• Comfortable in a large monorepo, with strong judgment on module boundaries and shared packages.
• Design systems experience: tokens, theming, and keeping component libraries honest as they scale.
• Familiarity with charting at scale: Lightweight Charts, D3, and/or canvas rendering.
• Accessibility in practice (WCAG) on dense screens.

Preferred

• SSR or edge rendering experience (Astro, Next, Remix) and web performance work.
• Experience with or opinions on when to avoid micro frontends.

Why it matters

UI correctness and freshness are treated as high consequence—the team emphasizes engineering rigor, correctness reviews, and verifying behavior to prevent trading-impacting errors.