Founding Product Engineer

San Francisco on site Until 10/1/2026 8+ years exp First posted August 2, 2026 Last posted August 2, 2026
Job description

About the Role

An early-stage AI-native B2B SaaS company building an AI-driven pricing and monetization platform is looking for a Founding Product Engineer to join as one of the first engineers on the team. This is a hands-on, high-ownership role where you will define architecture, own entire product modules end-to-end, and work directly with customers and leadership to shape how the product evolves.

The platform helps B2B companies continuously optimize their pricing lifecycle — covering packaging design, scenario simulation, quote recommendations, deal coaching, discount governance, and more. You will be instrumental in moving core financial logic server-side, extending a typed pricing ontology, and ensuring every feature can be driven by LLM agents.

This role is on-site in San Francisco, CA. US work authorization is required; visa sponsorship is not available.

What You'll Do

  • Own whole product modules end-to-end: scope with customers, design versioned APIs, build the UI, ship, and iterate.

  • Design and evolve architecture for agentic AI systems across Slack bots, terminal UIs, web interfaces, and vendor integrations.

  • Ensure product features are drivable by LLM agents via MCP/FastMCP server endpoints 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 — with Customer, Contract, and Quote on the roadmap).

  • Lead technical discussions and architectural reviews to keep systems robust, extensible, and secure.

  • 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; prioritize root-cause analysis for production issues.

  • Adopt and continuously improve an AI-native SDLC where agents assist with code generation and automated review gates.

What We're Looking For

Must-haves:

  • 8+ years of software engineering experience, with demonstrated 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 modern stack).

  • Proven track record of shipping end-to-end modules: customer scoping → versioned API design → React UI → production delivery.

  • Credible frontend range with React and TypeScript; able to ship a clean, polished UI independently.

  • Experience designing server-side business logic, versioned APIs, and ensuring testing, observability, and deployment for AI-driven features.

  • Experience building or integrating AI-assisted features and agent-driven workflows (e.g., LLM-driven interfaces, MCP-like endpoints).

  • Familiarity with B2B SaaS monetization concepts: pricing models, packaging, and quoting.

  • High standards for correctness, especially around financial logic.

  • Authorized to work in the United States without visa sponsorship.

Nice-to-haves:

  • Experience building MCP servers or tooling for LLM agents.

  • Background in billing, CPQ, metering, or pricing systems.

  • Experience with data-dense frontend components and/or conversational interfaces.

  • Familiarity with data residency, SOC 2, or GDPR-compliant development practices.

  • Prior experience as a technical founder, co-founder, or early employee who shipped a 0-to-1 B2B product to paying customers.

Compensation & Benefits

  • Salary: $200,000 – $250,000 USD per year

  • Early-stage equity commensurate with a founding-team role

  • Opportunity to shape product, engineering culture, and company direction from day one

Location

This is an on-site role based in San Francisco, CA. Candidates must be willing and able to work in person. US work authorization is required; the company does not offer visa sponsorship.

About this role

Summary

Develop end-to-end product modules, architecture, and AI features for SaaS platform.

Job title

Founding Product Engineer

Experience level

8+ years

Minimum experience

8+ years exp

Industry

software

Location requirements

on-site in san francisco, usa work authorization required

Salary

$200k–$250k

Management role

No

Skills & keywords

Required skills

fastapipythonmongodbreacttypescriptapi designai integration

Preferred skills

mcp serverspricing systemsconversational interfacesgdpr complianceearly employee experience

Specializations

backendapi designreacttypescriptai-driven features
Locations

Structured locations inferred from the posting.

San Francisco, CA, USA

On-site City