| Location | San Francisco, CA |
FERMÀT is the AI native commerce platform that optimizes shopping experiences, leading to best-in-class shopper engagement and conversion. We help brands transform clicks into conversions with dynamic, personalized shopping experiences-built and optimized in minutes.
Backed by VMG, Bain Capital Ventures, Greylock, QED, and named The Information's #1 commerce startup, we're a 70+ person team based in SF, Austin, NYC, and Bangalore. As a fast-growing Series B company, we're building the infrastructure for the future of online retail-and we're just getting started.
About the Role:
We're searching for a product‑minded Software Engineer to help build out Pierre, FERMÀT's AI Agent, into a production‑grade intelligence engine that powers personalization, automation, and operational insights across our commerce platform. You will design and build LLM‑powered features end‑to‑end: orchestration (tools/agents/function‑calling), retrieval, evaluations and productionization (APIs, observability, cost/latency). If you love turning ambiguous problems into shipped experiences-and you have experience taking AI products to market in the last 12 to 18 months, this role is for you.
What You'll Work On:
• Take AI products to market: prototype quickly, instrument, A/B test, and iterate based on quality, conversion impact, latency, and cost. • Own LLM orchestration: multi-agent systems, tool use, function‑calling, structured outputs, routing, context windows, retrieval and evals. • Build evaluation & observability: golden datasets, automated evals, prompt/version management and monitoring. • Productionize reliably: scalable APIs/services, workers/queues, caching and provider failover. Optimize performance while keeping costs reasonable. • Data foundations: integrate first‑party events and catalog data; respect data contracts. • Vendor strategy: evaluate and integrate multiple model providers (e.g., OpenAI, Anthropic, Google) while tracking quality, cost, and reliability. • Raise the bar: document best practices, lead design reviews, and mentor engineers on AI patterns.
What We're Looking For:
4+ years of professional software engineering experience. 12-18 months building and shipping LLM‑powered products (from prototype to GA) with meaningful customer adoption. Please include links, demos, or a brief write‑up if possible. Strong Python and TypeScript experience. Solid systems design and API fundamentals. Hands‑on with LLM APIs, embeddings, vector databases, retrieval patterns and agent/tool design. Pragmatic prompt engineering and prompt/version control. Production chops: cloud (GCP), containers, CI/CD, monitoring/alerting; comfort owning services in prod. Product sense, clear communication, and a bias to ship. Nice to Have: • E‑commerce, recommendations, ranking or ads experience. • Experience with streaming responses, Streamable HTTP/SSE/WebSocket patterns for real-time AI interactions. • Real‑time personalization and event pipelines (e.g., Kafka, pub/sub). • Front‑end (React) skills for rapid prototyping of AI UX. • Experimentation/analytics tools (e.g., PostHog or similar).
Benefits:
• Competitive salary + equity package • Comprehensive health, dental, and vision insurance for you and all your dependents. • Retirement benefits: US: 401(k) plan with 4% matching; India: Provident Fund with 12% matching. • 4 months of paid parental leave • Unlimited PTO policy (with minimum 5 days PTO / quarter!)