Full-Stack Engineer: AI Agents Infra & UX Lead (SF)

Ersilia; San Francisco (CA); In loco; USD 200.000 - 300.000; Tempo pieno

Descrizione del lavoro

Ersilia in San Francisco is seeking a Full-Stack Engineer to own product experiences and agent infrastructure across data, UI, and SDK layers. You will interact with customers, define what to build, implement it, and iterate until the experience is strong and reliable.

The role combines platform engineering with customer-facing work (approx. 30%). You will shape large-scale investigations, verify agent changes, and craft intuitive 1000+ step reasoning trajectories for developers.

Competenze

• Experience building and scaling end-to-end production systems, from data layer to UI.
• Hands-on experience building with LLMs or agents.
• Comfort working directly with customers to understand their needs and solve real-world problems.

Mansioni

• Shape how our Agent runs large-scale parallel investigations across production traces, merging failure modes, tool errors, regressions, and drift signals into a single actionable answer.
• Build hosted simulated environments for stateful agent evals, trajectory replay against changed agents, and monitors for unintended behavior.
• Design how engineers understand long traces, tool calls, decisions, and failures: making a thousand-step reasoning trajectory legible in minutes.
• Build the swarm UX so engineers can watch parallel investigations, redirect investigators that go down the wrong path, and consume findings without reading hundreds of reports.
• Own the improvement loop: the workflows that turn production trajectories into datasets, judges, and regression checks so the path from found problem to verified fix feels like one motion.
• Build and maintain the SDK and terminal-first experience so agent development sessions can summon our agent as a subagent mid-development.
• Own platform infrastructure: workspaces, roles, permissions, billing, usage, and limits for teams running many agents across many environments.

Conoscenze

End-to-end systems

LLMs

Customer-facing

Strumenti

Databricks

Descrizione del lavoro

Ersilia in San Francisco is seeking a Full-Stack Engineer to own product experiences and agent infrastructure across data, UI, and SDK layers. You will interact with customers, define what to build, implement it, and iterate until the experience is strong and reliable.

The role combines platform engineering with customer-facing work (approx. 30%). You will shape large-scale investigations, verify agent changes, and craft intuitive 1000+ step reasoning trajectories for developers.