Senior Product Engineer

Responsibilities

• Own Sauna’s product surface across delegation, progress tracking, approvals, undo, memory, routines, apps, connected Saunas, onboarding, and billing.
• Design and ship frontend-centered product experiences from rough direction through implementation, feedback, and iteration.
• Build full-stack features spanning interaction design, client architecture, API routes, database migrations, user interfaces, and analytics.
• Develop performant local-first interfaces using caching, invalidation, optimistic updates, and IndexedDB persistence.
• Create realtime, streaming, multiplayer, and cross-platform experiences across web, iOS, Slack, email, iMessage, and Superhuman.
• Own features after launch and make detailed decisions around loading states, empty states, error handling, keyboard shortcuts, and visual polish.

Requirements

• Experience shipping and owning complex web products, including multiplayer experiences, large-data applications, streaming interfaces, or realtime UIs.
• Deep React expertise, including state management, context or store usage, rendering behavior, and reusable component design.
• Ability to own full-stack features end to end, including migrations, routes, data fetching, UI, and analytics.
• Strong understanding of performance, caching, invalidation, optimistic updates, and avoiding duplicated network requests.
• Product judgment, visual taste, autonomy, and willingness to work from rough direction without waiting for a complete specification.
• Heavy personal use of AI tools and informed opinions about their strengths and limitations; professional AI-product experience is not required.
• Preferred experience includes LLM-based product interfaces, realtime collaboration with CRDTs or similar systems, local-first architectures, design or strong visual sense, and founding or early frontend engineering.

Benefits

• Base salary of $180K–$240K plus meaningful early-stage equity, health and dental insurance, 401(k), generous PTO, gym budget, and lunch.
• Full-time, in-person work five days per week at the company’s Presidio office in San Francisco.
• Candidates must be based in the Bay Area or willing to relocate before starting.
• The hiring process may include a paid in-person work trial lasting from a few days to two weeks.