Founding Full-Stack Engineer

About the company

Our client is a seed-stage, venture-backed AI startup in San Francisco building production agents for a regulated professional-services industry. Their product drafts, reviews and negotiates commercial contracts, and has already handled a large volume of deal work for technology companies. The team is around five people, backed by a well-known accelerator and a group of consumer and fintech founders, with its engineering hub in San Francisco.

The role

You are one of the first engineers, building agentic systems end to end: the harness, the evaluations and the interfaces that have to be reliable enough for lawyers to sign off on. You also ship ordinary full-stack product work — review queues, redline and diff views, agent chat, operations dashboards — and you sit next to the lawyers who use it, so you can scope, ship and get feedback the same day. Two hires are planned and they are meant to complement each other: one leaning front end and product, one leaning backend and observability. Everyone works the whole stack.

What you'll do

• Build and iterate on agentic systems end to end — harness engineering, agent evaluations and agent interfaces
• Ship full-stack features from database to UI, including review queues, redline and diff views and agent chat
• Build integrations with chat, email, document and e-signature platforms and billing providers
• Improve observability, evaluations and infrastructure so the agents stay trustworthy at scale
• Work directly with the domain experts sitting next to you to scope problems and ship the same day

Nice to have

• Roughly 3 to 7 years as a full-stack engineer — the client cares about self-sufficiency far more than the exact number
• Time at a VC-backed, high-growth startup after a spell at a larger or more mature company
• A STEM or computer science degree
• Experience in legal tech or another regulated industry such as fintech, health or insurance
• Backend observability experience — logging, tracing, evaluations and reliability
• Experience working directly with users to scope technical problems

Tech stack

TypeScript, React and Next.js on the front end; Node.js and PostgreSQL on the back end. Agent harnesses, agent evaluations and agent UIs, plus integrations with chat, email, e-signature and billing.

Compensation & logistics

• $180k–$250k base + 0.1–0.6% equity
• On-site five days a week in San Francisco (SoMa); relocation support offered
• No visa sponsorship of any kind and no visa transfers — candidates must be legally authorized to work in the United States and not need visa sponsorship or a visa transfer now or in the future
• Occasional international travel to work alongside the CTO
• 2 to 3 hires planned
• Full-time