Staff Software Engineer, PEO Benefits

Gusto • Denver, CO;San Francisco, CA;New York, NY • 1d ago

Why This Job is Featured on The SaaS Jobs

This Staff Software Engineer role sits at an intersection that matters in SaaS: a scaled platform expanding into a new product line with regulated, integration-heavy workflows. Building benefits and PEO capabilities typically requires deep systems thinking around eligibility, plan configuration, carrier connectivity, and operational tooling, which are recurring patterns in vertical SaaS and fintech-adjacent products. The listing also signals meaningful greenfield surface area inside an established codebase, a combination that is relatively uncommon.

From a SaaS career standpoint, the work maps to durable skills: designing APIs that support evolving product requirements, shipping end-to-end across frontend and backend, and making architectural decisions that hold up under real customer volume. The emphasis on post-launch ownership and iteration reflects how mature SaaS teams measure engineering impact over time, not just at release. Exposure to AI-assisted development practices adds a modern productivity and quality dimension that is increasingly expected across SaaS engineering orgs.

This role is best suited to senior engineers who prefer broad product ownership over narrow component work, and who are comfortable influencing direction across engineering and product partners. It will appeal to those who enjoy complex domains and mentoring as part of their day-to-day, while still staying hands-on in a full-stack environment.

The section above is editorial commentary from The SaaS Jobs, provided to help SaaS professionals understand the role in a broader industry context.

Job Description

About the Role:

We're looking for seasoned full-stack software engineers to join Gusto’s PEO Benefits team.

Gusto is standing up a Professional Employer Organization (PEO) — one of the biggest new bets in the company — and Benefits is the anchor of the offering. At the core is a national Master Health Plan that can unlock ~20–25% lower healthcare costs for small businesses through pooled purchasing power, something most PEOs can't pull off in year one. You'd be joining the engineering team building the systems that make that real.

This is rare greenfield scope inside a company with real scale and real customers. You get to make foundational architectural decisions, not maintain someone else's.

As a Staff Software Engineer, you'll operate across the full product lifecycle: shaping features from early spec and design through to launch and long-term iteration. That means writing clean frontend code, designing and building reliable backend APIs, influencing product direction, and taking ownership of what happens after a feature ships.

If you're drawn to work that combines technical craft with real-world impact — helping power the livelihoods of millions using Gusto products — join us!

Here’s what you’ll do day-to-day:

Design, build, and test the Gusto PEO Benefits experience - the benefits shopping and plan-recommendation flows, carrier integrations, MCP tools, agents that automate operational and customer support processes
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 Management, Data, Design, and Platform Engineering teams to understand customer pain points, come up with solutions, and then prototype, iterate, and launch daily
Build products that our customers genuinely love

Here’s what we’re looking for:

Successful applicants typically have 8+ years of software development experience
PEO Expertise (Preferred): 3+ years of experience with PEO, with direct experience building PEO flows in a high-growth environment.
Experience owning multi-quarter projects that solve complex engineering problems and make measurable customer impact at scale
Experience driving large, cross-functional projects end-to-end through ambiguity — scoping, sequencing, and unblocking without needing the problem pre-broken-down; aligning multiple stakeholders and working with multiple teams
Experience leveraging AI tools or systems to accelerate development, improve testing, and deliver new product capabilities
Curiosity and experimentation with emerging AI frameworks, applying and sharing best practices to evaluate and scale AI use safely across teams
Ability to mentor engineers to maximize their performance and impact

Others:

Experience in, or interest working in, Ruby on Rails
Appreciation for a collaborative, test-driven environment
Ability to build well-structured, maintainable, well-documented code
Ability to effectively communicate across engineering teams and with business stakeholders

Please note that travel to Gusto's office for onboarding is required for this position. If you have any questions regarding this requirement, please share with your recruiter.

Our cash compensation amount for this role is targeted at $163,000–$204,000 in Denver & most remote locations, and $197,000–$247,000 for San Francisco & New York. Stock equity is additional. Final offer amounts are determined by multiple factors including candidate experience and expertise and may vary from the amounts listed above.

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