Founding Product Engineer

This is a founding engineering role at an early-stage B2B SaaS startup building an AI-driven pricing and monetization platform. You'll own entire product modules end-to-end — from architecture through shipped UI — working directly with customers and leadership to shape the product. Financial precision, technical leadership, and comfort with ambiguity are central to success here.

What You'll Do

• Scope, design, build, and iterate on whole product modules independently, including versioned APIs and React UIs.
• Design and evolve architecture for agentic AI systems spanning Slack bots, terminal interfaces, web surfaces, and vendor integrations.
• Ensure features are drivable by LLM agents via MCP/FastMCP servers and conversational interfaces.
• Move pricing and business logic off the client into backend services to preserve financial fidelity.
• Extend and maintain a typed pricing ontology using Pydantic models (e.g., SKU, Proposition, Persona, Pricing, Customer, Contract, Quote).
• Lead architectural reviews and establish testing, observability, deployment, and performance monitoring practices for AI-driven features.
• Mentor peers, influence product strategy, and help set engineering culture and best practices.
• Treat money-handling code as load-bearing infrastructure and drive root-cause analysis for production issues.
• Contribute to an AI-native SDLC where agents assist with code and automated review gates.

• 8+ years of software engineering experience with proven ownership of full product areas at startup or staff-level scope.
• Deep backend expertise with production experience in FastAPI, Python, and MongoDB (or a comparable stack).
• Credible full-stack range: able to design versioned REST/GraphQL APIs and ship polished React + TypeScript UIs independently.
• Track record of taking ambiguous customer problems to shipped features without a dedicated PM.
• Experience with B2B SaaS monetization concepts: pricing models, packaging, quoting, billing, or CPQ.
• Experience building or integrating AI-assisted features and agent-driven workflows (LLM interfaces, tool-use endpoints, etc.).
• High standards for correctness, especially around financial logic.
• Nice to have: Built MCP servers or tooling for LLM agents.
• Nice to have: Experience with billing, CPQ, metering, or usage-based pricing systems.
• Nice to have: Familiarity with SOC2/GDPR-compliant development practices.
• Nice to have: Prior experience as a technical founder or early employee who shipped a 0-to-1 B2B product to paying customers.
• Must be authorized to work in the United States; visa sponsorship is not available.

Salary range: $200,000 – $250,000 USD annually. Equity participation expected at this founding-team scope. Visa sponsorship is not available.

Location

On-site in San Francisco, CA. Remote work is not available for this role.