Senior Backend Engineer, Shopping Agents

San Francisco · Full‑time · Onsite

About Us

Sage AI Labs is building the infrastructure that lets AI agents transact on the open web. It tackles one of the few genuinely unsolved problems left in commerce, and whoever solves it sets the defaults everyone else builds on top of. The company was founded by Sebastian Thrun (founder of Google X and Waymo, Udacity) and is backed by leading venture and strategic investors.

About the Role

We build agents that shop for you. They find products across the open web and complete the purchase end‑to‑end—real carts, real payments, and real systems built to stop them. You would own the architecture, code, deploys, monitoring, and on‑call for systems that transact around the clock, working directly with our CTO.

What You’ll Own

• Checkout agents: frontier‑model computer‑use agents driving live checkouts at scale, plus the machinery that keeps them standing when the ground moves.
• Ingestion at scale: take product ingestion from hundreds of sources to thousands using self‑generating, validating, and monitoring infrastructure.
• Search and ranking: embedding‑based retrieval, LLM query understanding, reranking, and caching across a constantly changing catalog.

What We’re Looking For

• 5+ years building backend and infrastructure systems, with strong Python skills.
• Experience owning production systems end‑to‑end: deploys, databases, observability, and on‑call responsibility.
• Track record of being paged and fixing the class of problem rather than just the incident.
• Enjoyment of adversarial problems where external actors actively work against the system.
• Commitment to correctness; these systems spend customers’ money, so silent failures are unacceptable.
• Ability to move forward without a finished spec in a small, fast‑changing team.

Nice to Have

• Built AI‑first products or LLM‑based agents in production, not just prototypes.
• Working knowledge of classic ML and deep learning sufficient to reason about retrieval and ranking.
• Background in e‑commerce, payments, or fraud and risk infrastructure.

Why This Role

Very few engineers get to own a category‑defining system while the category is still being defined. This seat is early‑stage; a year from now the problem will have a standard answer, and we intend to be the ones who write it.

Compensation and Benefits

• Meaningful early‑stage equity.
• Medical, dental, and vision coverage; other benefits.