Founding Software Engineer
Copperlane, San Francisco, California
- Pay
- $160K–$240K / year
- Work type
- Not stated
- Level
- Not stated
- Area
- Software engineering
- Posted
- Sep 21, 2026
About the role
The Role
We're looking for a founding software engineer (member of technical staff) who is obsessed with building agentic AI systems and wants to ship real product from day one. You'll work across the stack but spend most of your time on backend systems, building and orchestrating AI agents that interact with borrowers, loan officers, and third-party platforms in a regulated industry.
This is not a "learn on the job quietly" role. You'll be in the room with customers, see how your code impacts their workflow, and iterate fast. This role is on-site in our San Francisco, CA office.
What You'll Work On
- Designing and building agentic AI pipelines: tool use, multi-step orchestration, evaluation, and reliability at scale
- Backend services in Python (FastAPI) on Aurora PostgreSQL and AWS
- Multi-tenant architecture with strong security and compliance boundaries
- Integrations with mortgage industry platforms (LOS systems, voice, messaging)
- Frontend experiences in React, Vite, and TanStack when the product calls for it
What We're Looking For
- Strong fundamentals in backend engineering (Python preferred)
- Hands-on experience building with LLMs: agent loops, tool calling, prompt engineering, evals
- Comfort with PostgreSQL, schema design, and migrations
- Exposure to multi-tenancy patterns, auth, or compliance-aware systems is a plus
- Bonus: sharp design sensibility and strong frontend skills (React, Vite, TanStack). We value engineers who care deeply about craft on both sides of the stack.
- High energy, low ego, genuine curiosity about how things work
- You care about the people using what you build
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