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Sr. UI Engineer

Joist Ai

Joist Ai

Design
Kolkata, West Bengal, India
Posted on Sep 18, 2025
Senior UI Engineer

About The Company

Joist AI is revolutionizing how Architecture, Engineering, and Construction (AEC) firms manage marketing and revenue operations. Our AI-powered platform streamlines proposal workflows and content operations so teams can collaborate faster and win more work.

About The Role

We’re looking for a Senior UI Engineer who obsesses over the last 5%: spacing that breathes, motion that informs, micro-interactions that feel inevitable. You’ll own front-end craft end-to-end; from exploratory prototypes in Figma to production-ready React components—bringing clarity and polish to complex, data-heavy workflows. This role partners closely with Product and Design to ship usable, accessible, and elegant experiences at startup speed.

What you’ll do

  • Design & ship delightful UI: Build responsive, accessible React interfaces with a focus on visual hierarchy, typography, spacing, and interaction finesse.
  • Prototype to learn: Create fast prototypes (Figma + code) to validate flows, micro-interactions, and edge cases before we over-invest.
  • Own the design system: Evolve our component library (tokens, theming, variants), document usage in Storybook, and raise the bar on consistency.
  • Make complexity feel simple: Translate dense requirements (RFP analyzers, editors, timelines, dashboards) into intuitive, low-friction flows.
  • Performance matters: Profile and optimize hydration, bundle size, virtualization, and perceived latency; measure with real user metrics.
  • Quality culture: Write tests (RTL, Jest/Vitest, Playwright), run visual regression, and champion code reviews focused on UX outcomes.
  • Partner across functions: Work with Product, Design, and Backend to sequence delivery, clarify scope, and land high-impact iterations.
  • Mentor through craft: Give incisive design and code feedback; model taste and practical judgment for the team.

Background we’re looking for

  • 6+ years building production web apps with modern React, TypeScript, and component architectures.
  • Proven track record shipping polished UI in a complex B2B product (workflows, editors, dashboards, or data-heavy apps).
  • Strong fluency with Figma, design systems, tokens, and accessibility standards.
  • Comfortable with state management (React Query/TanStack, Zustand/Redux), routing, form patterns, and WebSocket/real-time UX.
  • Experience with Storybook, Tailwind/shadcn/ui (or similar), and Framer Motion (or equivalent) for purposeful micro-interactions.
  • Demonstrated ability to decompose ambiguous UX problems and communicate trade-offs clearly with stakeholders.
  • Bonus: data-viz (Recharts/D3), collaborative editors, PDF/Word rendering, canvas/RTEs, or AEC/enterprise SaaS.

Experience We’d Be Particularly Excited About

  • A portfolio with before/after examples that explain why your decisions improved comprehension or task time.
  • Design-system stewardship at scale (tokens, dark mode/theming, accessibility audits).
  • Turning messy domain logic into simple, progressive workflows.
  • Instrumenting UX with product analytics and using data to drive iteration.

Our tech stack (you’ll touch)

React + TypeScript

  • Tailwind + shadcn/ui
  • Redux
  • Playwright/RTL/Jest/Vitest Backend APIs: FastAPI
  • AWS (Lambda, RDS, S3, Step Functions)
  • WebSockets

What to expect

We run a rigorous, fast interview process focused on craft, judgment, and impact:

  • Intro chat (30 min): your background, the role, mutual fit.
  • Portfolio walkthrough (45–60 min): deep dive on 2–3 projects—goals, constraints, your decisions, measurable outcomes.
  • Practical exercise: a small UI task emphasizing interaction design, accessibility, motion, and code structure.
  • Review & team conversation (60 min): discuss your approach, trade-offs, and how you work cross-functionally.

If you’re excited to make sophisticated workflows feel effortless—and you care about the tiny details users can feel but can’t name—we’d love to talk.