Mid-Level AI Engineer

Wintermeyer Ventures; San Francisco (CA); On-site; USD 150,000 - 250,000; Full time

Job summary

Wintermeyer Ventures in San Francisco is seeking an AI Engineer to own the production AI layer of its commerce-focused SaaS product. You will build and improve systems used by merchants, make key architecture decisions, and help the team ship reliable AI features.

You will turn ambiguous product needs into practical AI solutions, ship to production regularly, and optimize latency and costs to scale for real merchants.

Qualifications

• Two to four years of experience building production LLM systems.
• Experience shipping an AI or ML system to real production users.
• Experience building LLM evaluation systems that identify regressions.
• A computer science degree or equivalent strong fundamentals.
• Experience in contract or freelance work, and at a startup in growth.
• Strong engineering track record via work, open-source, papers, or side projects.
• Familiarity with ML or fine-tuning, and ideally commerce/ Shopify/ marketplace products.
• Experience with Python, LLMs, React, TypeScript, and Node.js.

Responsibilities

• Build end-to-end AI systems, including prompts, retrieval, tool use, agent orchestration, and fine-tuning when useful.
• Create evaluation systems that test model changes and catch regressions before release.
• Improve latency and operating costs so AI features perform reliably at merchant scale.
• Turn ambiguous product needs into solutions by identifying whether the issue is with the model, data, or user experience.
• Ship to production regularly and monitor how features perform with real users.

Skills

Python

LLM systems

React

TypeScript

Node.js

Education

Computer science degree

Job description

About the Role

Join an early-stage commerce-focused SaaS company as an AI Engineer owning the production AI layer of its product. You will build and improve systems used by merchants, make key architecture decisions, and help the team ship reliable AI features.

What You’ll Do

• Build end-to-end AI systems, including prompts, retrieval, tool use, agent orchestration, and fine-tuning when it is useful.
• Create evaluation systems that test model changes and catch regressions before release.
• Improve latency and operating costs so AI features perform reliably at merchant scale.
• Turn ambiguous product needs into solutions by identifying whether the issue is with the model, data, or user experience.
• Ship to production regularly and monitor how features perform with real users.

What We’re Looking For

• Two to four years of experience building production LLM systems, with strong hands‑on Python skills.
• Experience shipping an AI or ML system to real production users, rather than only building research prototypes or internal demos.
• Experience building LLM evaluation systems that have identified regressions.
• A computer science degree or equivalent strong computer science fundamentals.
• Experience in contract or freelance work, and at a startup, preferably one that has reached a growth stage.
• A track record of strong engineering, demonstrated through work experience, open‑source contributions, papers, or side projects.
• Familiarity with ML or fine‑tuning, and ideally commerce, Shopify, or marketplace products.
• Experience with Python, LLMs, React, TypeScript, and Node.js.

Compensation & Benefits

Base salary is $150,000 to $250,000 USD annually. Visa sponsorship is not available.

Location

This is an on-site role in San Francisco, United States.