Senior Staff Software Engineer, Gusto Agent & Partner Experiences (API)

Gusto

San Francisco, CA - HybridFull-time$213k2026-10-15 → 2026-11-10

Hybrid

Core

Senior technical leader bridging API and AI worlds to build and scale a payroll platform for developers and AI agents.

Role type

Senior Staff Software Engineer (API & AI Integration)

Builds

Public-facing APIs, agent-facing tools, and payroll platform infrastructure for third-party developers and AI agents.

Domain

Fintech / Payroll / AI Agents

Required skills

Ruby, Ruby on Rails, API design, Platform architecture, Technical leadership, Mentoring, Reliability engineering, Observability, Troubleshooting

Preferred skills

Payroll domain knowledge, Agent tooling (MCP servers, function definitions), GraphQL at scale

About Gusto

At Gusto, we're on a mission to grow the small business economy. We handle the hard stuff — payroll, health insurance, 401(k)s, and HR — so owners can focus on their craft and their customers. With teams in Denver, San Francisco, and New York, we support more than 500,000 small businesses nationwide and are building a workplace that reflects the people we serve.