Founding Product Engineer

Wwshemi; San Francisco (CA); On-site; USD 200,000 - 300,000; Full time

Job summary

Wwshemi, an early-stage consumer AI company, is seeking its founding product engineer to own an AI assistant and its end-to-end user experience across mobile and web. You will shape agent behavior, interfaces, and evaluation systems, ship features with experiments and flags, and lead with hands-on engineering while growing the team.

As a founding member, you will collaborate with researchers and designers to craft delightful user experiences, own the product vision, and drive robust, scalable

Qualifications

• 4+ years of software engineering in AI products.
• Experience building agents with tool use, memory, and long-running conversations.
• Experience with evaluation systems used for shipping decisions.
• Proficient in full-stack TypeScript/React/Next.js and Postgres.

Responsibilities

• Build the agent decision-making layer, including tool-calling loops, memory, context assembly, prompt design, and model routing.
• Create evaluation infrastructure with conversation replay, turn-level assessments, and regression suites to guide release decisions.
• Own product experiences across mobile and web, from onboarding and initial interactions to ongoing use, group conversations, approvals, and trusted networks.
• Ship features end to end, using experimentation and feature flags to measure outcomes and improve the product.
• 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 use feedback and product data to prioritize improvements.
• Set engineering standards and help grow the team while remaining hands-on.

Skills

AI product experience

Full-stack development

TypeScript

React

Next.js

Postgres

Product impact

Tools

OAuth

Payments integration

Browser automation

APIs

MCP servers

Tool calling

Job description

About the Role

Join an early-stage consumer AI company as its founding product engineer, with ownership of an AI assistant and its end-to-end user experience. You will work across agent behavior, product interfaces, and evaluation systems to help make everyday tasks easier for users.

What You'll Do

• Build the agent decision-making layer, including tool-calling loops, memory, context assembly, prompt design, and model routing.
• Create evaluation infrastructure with conversation replay, turn-level assessments, and regression suites to guide release decisions.
• Own product experiences across mobile and web, from onboarding and initial interactions to ongoing use, group conversations, approvals, and trusted networks.
• Ship features end to end, using experimentation and feature flags to measure outcomes and improve the product.
• 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 use feedback and product data to prioritize improvements.
• Set engineering standards and help grow the team while remaining hands-on.

What We're Looking For

• At least 4 years of software engineering experience at an AI product company, AI lab, or consumer product company shipping products at scale.
• Production experience building agents with tool use, memory, and long-running conversations, along with evaluation systems that inform shipping decisions.
• Full-stack experience with TypeScript, React, Next.js, and Postgres.
• Experience with third-party APIs, OAuth, payments, or agent tools such as function calling, MCP servers, and browser automation.
• A record of owning features end to end and demonstrating measurable product impact.
• Strong product judgment, consumer experience sensibility, and fluency with AI-assisted development, including verifying and owning shipped work.
• Experience leading a growing engineering team while staying hands-on, and evidence of sustained contribution at an employer or deep technical expertise.
• Post-training or fine-tuning experience is a plus.

Compensation & Benefits

Base salary: $200,000 to $300,000 annually. Visa sponsorship is not available.

Location

On-site in San Francisco, California.