Senior Product Engineer – Autonomous AI Assistant (On‑Site)

About the role

Own the product surface of an autonomous AI assistant with the founding team – shaping React architecture, real‑time UX, and full‑stack features from idea to production. You will be the senior frontend‑primary engineer responsible for the entire product experience that integrates with Slack, Gmail and Linear.

Key responsibilities

• Define and drive frontend architecture across the product using React, Next.js, TypeScript and TanStack Query, establishing patterns rather than inheriting them.
• Build complex, high‑performance UI including multiplayer surfaces, large‑data views, streaming and real‑time interfaces that operate under production load.
• Own full‑stack feature delivery end‑to‑end – from API routes and database migrations to UI and analytics – without relying on a dedicated backend engineer.
• Implement state‑management and rendering optimizations at scale, explaining caching, invalidation and optimistic‑update strategies.
• Make product decisions on vague ideas, ship a working first version without a PRD, and iterate based on feedback.

Required profile

• Deep production expertise in React, Next.js and TypeScript, with concrete examples of rendering‑optimization decisions in shipped products.
• Background at an AI‑native company or an elite startup (e.g., Notion or Linear calibre) and can name personal ownership of key features.
• Experience shipping and owning a complex web product (multiplayer, large‑data, streaming or real‑time UI) with documented scaling decisions.
• Ability to deliver full‑stack features end‑to‑end – API routes, database migrations, UI and analytics – without a dedicated backend.
• Publicly inspectable evidence of work (personal site, live product, public repo or contribution to a design system); no portfolio means no submission.
• Based in San Francisco or willing to relocate for a 5‑day‑a‑week onsite role.
• Open to a one‑week paid in‑person trial assessment; roughly 70 % of trial candidates convert to full‑time.

Required skills

• React
• Next.js
• TypeScript
• TanStack Query
• API routes
• Database migrations
• Real‑time UI
• Multiplayer interfaces
• Streaming data handling