Senior Software Engineer, Technology

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.

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.

We are seeking a Staff Software Engineer to join our People Technology team as the dedicated architect and hands on engineer behind PeopleOS — our AI-native internal HR platform — and the broader suite of custom tools and integrations that power our People tech ecosystem. In this role, you will design, build, and ship software that directly shapes how every Gustie experiences HR, from recruiting and onboarding to performance and offboarding.

The ideal candidate is a hands-on full-stack engineer and problem solver who thrives in ambiguity, cares about the employee experience, and wants to see their work used every day by real people.

The People Solutions team is transforming how Gusto supports its people by pairing cutting-edge AI with smart automation. We build — not just configure — the systems that power People programs and processes. We optimize workflows, enhance service delivery, and free up teams to focus on meaningful, high-impact work to support a more responsive, efficient, and future‑ready people experience.

• Be the technical owner for PeopleOS, our internal AI-powered HR platform that was built with the purpose of enhanced Gustie experiences for people programs and a more efficient People team with features like the Offer Workflow Engine, People Home Base portal, Celebration tools, and automated Talk Track generation
• Partner directly with People Ops stakeholders to translate workflows into working software driving technical design, implementation, UAT support, and release

• Design, build, test, and maintain integrations across Workday, Greenhouse, Lattice, Slack, and Google Workspace
• Build and maintain custom MCP (Model Context Protocol) servers that give AI agents structured access to People Systems data where no native tool MCP exists

• Integrate the Anthropic API (Claude) to build intelligent internal tools including QPR coaching agents, HR front door chatbots, and ticket deflection workflows
• Design prompts, handle structured outputs, and build safe, reliable AI-assisted workflows for People Ops use cases

• Document integration specs, data mappings, and system configurations in Notion
• Participate in Jira sprint planning and demo work to stakeholders bi-weekly
• Troubleshoot issues, identify root causes, and proactively implement corrective actions across the portfolio

• 7+ years of full-stack software engineering experience, with production-quality work in Python, Type Script/Node.js, or both
• Strong experience building and consuming REST APIs — including OAuth flows, rate limiting, pagination, and error handling
• Demonstrated ability to integrate SaaS platforms (bonus: Workday, Greenhouse, Slack, or Google Workspace)
• Comfort with AI/LLM API integration — Anthropic Claude, OpenAI, or equivalent — including prompt design and response parsing
• Experience shipping internal…