The opportunity
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.
What you'll do
Design and maintain evaluation frameworks across offline and online: environments — including golden datasets, LLM-as-judge pipelines, and production replay — while establishing regression gates and end-to-end observability and tracing for agent runs
Design, build, and test Gusto core platform services: communications, reporting, dashboards, access, workflows, risk, payments, and compliance capabilities, among others
Mentor other engineers to help solve some of the hardest technical problems: out there in very complex domains and at a large scale
Help scale one of the largest Ruby/Rails and Javascript/React applications in the world
Collaborate with our Product Engineering, Product Management, Data, and: Design teams to understand customer pain points, come up with solutions, and then prototype, iterate, and launch daily
Build platforms that engineering teams rely on, and trust to deliver products: that our customers genuinely love
What they're looking for
- Successful applicants typically have 8+ years of software development experience
- Hands-on experience taking AI/LLM capabilities to production: agent orchestration, tool integration, retrieval, and evaluation/feedback loops that keep AI improving safely
- AI fluency: fluent, daily use of AI coding assistants (e.g., Claude Code, or: equivalent AI harness) across the development lifecycle — writing, reviewing, debugging,
- and documenting code: with strong judgment on when to apply them, how to evaluate output quality, and how to stay current as the tooling evolves
