Senior Design Engineer

Senior Design Engineer

Summation is building an AI Business Planning Platform for CFOs and finance teams. We combine a real-time modeling layer with Addison, our AI calculation engine, to turn messy enterprise data into decision-grade insights. Customers use Summation to model scenarios, explain variances, and automate weekly and monthly reviews.

Roles & Responsibilities

• Build production UI in React and TypeScript for Summation's web app

• Lead the Summation Design System: tokens, components, theming, accessibility, docs, and release workflow

• Prototype end-to-end product ideas in code, validate with real data, and graduate winners into production

• Craft motion and micro-interactions that clarify meaning and reduce cognitive load

• Translate flows and states from Figma into resilient, testable components with strong state management

• Drive UI performance: bundle hygiene, code-split plans, rendering strategy, perceived latency

• Partner with data visualization to express complex financial concepts with clarity

• Establish guardrails: lint rules, Storybook checks, accessibility checks, visual regression in CI

• Mentor engineers and designers on interaction patterns, system thinking, and front-of-frontend craft

• Contribute to product quality across the stack through reviews, pairing, and high-signal documentation

You will love this role if you

• Love working across design and code, and care about the details users feel

• Think in systems: tokens, states, variants, docs, upgrade paths

• Prototype ideas fast and are comfortable deleting code after an experiment

• Believe accessibility, performance, and clarity are product features

• Enjoy collaborating with PMs, designers, and backend engineers in a high-context startup

Required experience

• 4+ years building production web UI with React and TypeScript

• Strong CSS fundamentals: layout, fluid type and spacing, responsive systems, motion

• Design system experience: tokens, component architecture, Storybook, documentation

• Data visualization in production using one of Recharts, D3, Visx, ECharts, or similar

• Accessibility and quality: semantic HTML, WCAG basics, keyboard and screen reader support, automated checks

• Figma fluency: components, variants, auto-layout, dev mode, and handoff

• Proven ability to take a concept from Figma to shipped code without heavy PM overhead

Nice to have

• Remix or Next.js, Tailwind, shadcn/ui

• Framer Motion for interaction design

• WebGL or Canvas experience for advanced interactions

• Visual regression and accessibility tooling in CI

• Experience in fintech, analytics, or complex data products