Founding Product Engineer

ABOUT THE ROLE Join a small product engineering team building a consumer AI assistant. As the founding product engineer, you will own the agent and user experience end to end, shaping how the assistant reasons, communicates, and takes action. WHAT YOU'LL DO - Build the agent decision-making layer, including tool-calling loops, memory, context assembly, prompts, and model routing. - Create evaluation infrastructure with conversation replay, turn-level judges, and regression suites to help assess product quality before releases. - Own product experiences across mobile and web, from onboarding and initial interactions to follow-ups, group conversations, and approvals. - Ship features from idea through experimentation and release, using feedback and product data to guide priorities. - Develop integrations with email, calendars, bookings, payments, and browser automation, including reliable tool use and user approval flows. - Review conversations, speak with users regularly, and help establish engineering practices and grow the team. WHAT WE'RE LOOKING FOR - At least 4 years of software engineering experience, including work at an AI product company, AI lab, or consumer product company shipping at scale. - Production experience building agents with tool use, long-running conversations, and memory, as well as evaluation systems that inform release decisions. - Full-stack skills with TypeScript, React, Next.js, and Postgres. - Experience with third-party APIs, OAuth, payments, or LLM agent tools such as function calling, MCP servers, or browser automation. - A track record of owning product features end to end and delivering measurable outcomes, with strong product and design judgment. - Fluency with AI-assisted development and strong fundamentals for validating shipped work; post-training or fine-tuning experience is a plus. COMPENSATION & BENEFITS Salary range: $200,000 to $300,000 annually. Visa sponsorship is not available. LOCATION On-site in San Francisco, California.