Founding Design Engineer

About the Role This is a founding-level, high-ownership position sitting at the intersection of design and engineering. You'll be the sole bar-raiser for frontend UX across a fast-moving, early-stage B2B SaaS company building an AI-powered pricing optimization platform. Your work will ensure that human-authored and agent-written UIs feel like one coherent, polished product — covering everything from the design system and component library to conversational surfaces on platforms like Slack and Microsoft Teams. You'll work shoulder-to-shoulder with the founders and a small, tight-knit engineering team, with enormous scope and direct influence over the product's quality and direction from day one. What You'll Do Own the design system end-to-end: design tokens, a shadcn/ui-based component library, and Tailwind CSS conventions applied consistently across the product suite. Define and enforce frontend patterns using React Query, React Hook Form, and Zod — ensuring agent-written PRs land consistent and polished by default. Shape conversational agent interfaces for constrained platforms (Slack Block Kit, Microsoft Teams Adaptive Cards), bringing the same visual and interaction quality as the core product. Codify accessibility standards — implement WCAG contrast rules and guardrails directly into brand guidelines and the codebase. Maintain and improve frontend tooling and quality: Biome configuration, Playwright E2E test coverage, and frontend performance optimization. Translate design intent into code: reusable component abstractions, motion (e.g., Framer Motion, Radix transitions), and tactile micro-interactions. Partner cross-functionally with founders and engineers to keep the frontend a thin, polished layer over the API. Integrate AI coding tools (e.g., Claude Code, Cursor) and custom lint/agent rules into the frontend workflow. What We're Looking For Must-haves (dealbreakers): 5+ years building product interfaces, with a portfolio of shipped features demonstrating high polish. Primary ownership of a production design system or component library (public repo, portfolio, or detailed walkthrough required). Deep expertise in React, strict TypeScript, Tailwind CSS, and component primitives (shadcn/ui, Radix UI). Authorized to work in the US — visa sponsorship is not available. Required skills & experience: Strong systems thinking: ability to translate visual decisions into tokens, component abstractions, and lint rules. Experience enforcing WCAG accessibility standards and integrating them into a living codebase. Hands-on experience with AI coding tools in production workflows (e.g., Claude Code, Cursor). Comfort acting as the sole frontend UX standard-setter across a company — you raise the bar, you own it. Nice to have: Experience building non-standard AI interfaces: streaming responses, generative canvases, human-in-the-loop views. Experience designing and shipping conversational interfaces or chatbots for B2B end-users. Familiarity with Slack Block Kit, Microsoft Teams Adaptive Cards, or CLI design patterns for constrained UI spaces. Experience with animation and UI state transition tooling (Framer Motion, Radix) to enhance perceived speed and polish. Compensation & Benefits Salary: $180,000 – $220,000 USD annually Founding team equity commensurate with early-stage, high-ownership role Direct impact on product direction and technical culture from day one Location This role is on-site in San Francisco, CA. The team works together in person; remote-only candidates are not a fit for this position.