Founding Design Engineer

About the Role This is a founding-level role at a seed-stage B2B SaaS startup in the pricing intelligence space. You will own the entire frontend design system, component library, and UI coherence layer across a product that ships fast with both human engineers and AI coding agents. This role is the sole bar-raiser for frontend quality and UX standards across the company. What You'll Do

• Define and maintain the design token system, component library, and frontend patterns that keep every shipped interface feeling like one cohesive product.
• Enforce frontend standards so that agent-written and human-written pull requests land consistently by default, using React Query, React Hook Form, and Zod.
• Own frontend tooling and quality, including Biome configuration, Playwright end-to-end coverage, and frontend performance.
• Translate design intent into component abstractions and lint rules to preserve coherence at scale.
• Build and iterate on conversational and AI-native interface patterns, including streaming responses and generative views.
• Integrate AI coding tools into the frontend workflow to accelerate delivery without sacrificing polish.
• Contribute to constrained UI surfaces such as chat-based or CLI-style interfaces where applicable. What We're Looking For
• 5 or more years building and shipping polished product interfaces, with a strong portfolio demonstrating that quality.
• Deep expertise in React, strict TypeScript, and Tailwind CSS, with hands-on experience with component primitives such as shadcn/ui and Radix UI.
• Prior ownership of a design system or component library in production, demonstrated through a public repo, portfolio, or detailed walkthrough.
• Experience defining and enforcing frontend patterns across a team, including with AI-assisted coding tools such as Claude Code or Cursor.
• A hands-on design/UX engineer mindset, not a product designer role.
• Familiarity with animation and UI state transitions (e.g., Framer Motion) to enhance perceived speed and polish is a strong plus.
• Experience building conversational interfaces or chatbots for B2B users is a plus.
• Experience with constrained UI spaces such as Slack Block Kit or Microsoft Teams Adaptive Cards is a plus.
• Authorized to work in the United States without visa sponsorship. Compensation & Benefits Base salary range: $180,000 to $220,000 USD annually. Equity participation is expected at this founding-team level. No visa sponsorship is available. Location On-site in San Francisco, California , five days per week. Candidates must be based in San Francisco or willing and able to relocate.