Founding Full-Stack Engineer (US)

We are looking for a Founding Full-Stack Engineer with 3, 7 years of experience to join a small, high-impact engineering team building agentic systems that power an AI-native law firm. You'll work across the entire stack, from PostgreSQL and Node.js on the backend to React and Next.js on the frontend, shipping agent harnesses, UIs, and integrations that lawyers use every single day. Moritz (YC W26) has handled $2B+ in contracts across 100+ companies and raised a $9M seed in four days from YC and the founders of Reddit, Instacart, Cruise, Dropbox, Gusto, and Runway. This is a founding-level role with significant equity (0.1, 0.6%) at a company still early enough for your work to materially shape the outcome.

What will you be doing?

• Building and iterating on agentic systems end-to-end, harness engineering, agent evaluations, and agent interfaces that must be reliable enough for lawyers to sign off on

• Shipping full-stack application features from database to UI, including client-facing surfaces, lawyer workspace tools (review queues, redline/diff views, agent chat), and operations dashboards

• Building integrations with Slack, email, document/e-signature platforms, and payment/billing providers to automate legal workflows

• Improving observability, evals, and infrastructure to ensure agents are trustworthy and reliable at scale

• Working directly with lawyers who sit next to you, scoping problems, shipping solutions, and getting feedback the same day