Staff AI Platform Engineer (LLM/Agent)

Gusto; New York (NY); Hybrid; USD 170,000 - 260,000; Full time

Benefits offered by this job

Office in NYC

Office in Denver

Office in San Francisco

Job summary

Gusto is seeking an experienced software engineer to own and evolve the Otto AI platform. You’ll work on an end-to-end stack including the agent runtime, tool layer, Rails/GraphQL backend, and CX-facing frontend.

The role involves expanding autonomous, tool-using actions with safe, auditable permissions, plus building robust evals and observability for production safeguards. Hybrid work in NYC/Denver/SF is expected.

Qualifications

• Typically 8+ years of software engineering experience, owning systems end-to-end.
• Experience shipping LLM-powered or agentic systems in production, including tool-calling/agents, retrieval, or evals.

Responsibilities

• Design and build across the Otto platform, including the runtime and agent graph, the tool/action layer, the Rails/GraphQL backend, and the advocate-facing experience, owning a meaningful slice end-to-end.
• Expand what the agent can safely do: autonomous, tool-using actions with human-in-the-loop approval, built on a secure, auditable identity and permissions model
• Build the eval and observability systems (LLM-as-judge + deterministic scorers, offline gates and online production monitoring) that let us change the agent in production weekly without regressing correctness or escalation behavior
• Work directly with LLMs, including prompting, tool/function design, retrieval, and the feedback loops that turn real advocate interactions into a better Otto
• Partner closely with Product, Data, Design, and our CX teams to turn advocate and customer pain into shipped capabilities
• Mentor engineers and set the bar for how we build agentic systems responsibly and at scale

Skills

LLM-powered systems

Agentic systems

Full-stack development

Backend services

LLM runtime

Tools

Ruby on Rails

JavaScript/React

GraphQL

Job description

Gusto is seeking an experienced software engineer to own and evolve the Otto AI platform. You’ll work on an end-to-end stack including the agent runtime, tool layer, Rails/GraphQL backend, and CX-facing frontend.

The role involves expanding autonomous, tool-using actions with safe, auditable permissions, plus building robust evals and observability for production safeguards. Hybrid work in NYC/Denver/SF is expected.