Senior Staff Software Engineer (Gusto Agent & Partner Experiences (Application Programming Interface)

Gusto; San Francisco (CA); On-site; USD 180,000 - 260,000; Full time

Benefits offered by this job

Medical, dental, and vision insurance

Free meals at the office

Paid time off and holidays

Job summary

Gusto is seeking a Senior Staff Software Engineer on the Agent & Partner Experiences team in San Francisco to be a technical leader shaping the platform. You’ll be hands-on in our complex Ruby on Rails codebase and coach others to deliver a high-quality developer experience.

You’ll bridge the API and AI worlds, design API contracts and agent-facing tools, and help developers embed payroll into their software.

Qualifications

• 12+ years of professional software development experience.
• Expert in Ruby and Rails with large Rails apps.
• Strong API and GraphQL experience.
• Experience mentoring and leading engineers.
• Ability to design reliable, scalable platforms.
• Payroll/fintech domain experience is a head start.

Responsibilities

• Lead technical strategy for the Agent & Partner Experiences team.
• Develop and scale the platform with Ruby on Rails.
• Design API contracts and agent-facing tools.
• Collaborate with developers and AI agents.
• Mentor engineers and raise the technical bar.

Skills

Ruby

Rails

GraphQL

API design

Platform thinking

Technical leadership

Mentoring

Observability

Tools

MCP servers

Public APIs

Job description

• As a Senior Staff Software Engineer on the Agent & Partner Experiences team, you’ll be a key technical leader responsible for influencing the team and broader organization as we build and scale our platform
• You’ll do this through a combination of hands-on development in our complex Ruby on Rails codebase and guiding others to deliver a high quality platform experience
• You’ll sit at the bridge between our API and AI world - turning a payroll platform built for developers into one that agents can reason about and act through
• Gusto Agent & Partner Experiences is a platform that allows developers to embed payroll directly into their own software using our APIs and allows AI agents to act on payroll on a customer’s behalf
• We’ve taken Gusto’s robust payroll infrastructure and made it available beyond Gusto itself - to third party developers and to the agents acting on their customers’ behalf
• Our vision is to enable anyone to build the best payroll product for their end customers - powering payroll for small and medium businesses across a variety of industries, from vertical SaaS to fintech and neobanks to AI-native products
• Identify and solve high-impact problems involving technical and organizational complexity that requires understanding and coordination across multiple domains
• Design the API contracts and agent facing tools our partners and AI agents build on, including what a good interface looks like when the caller is an agent model
• Engage directly with our developer-customers and internal agent partner to deliver a remarkable payroll product
• Ship code. Clean, tested, and performant
• Level up the craft of software engineering across the organization by providing technical guidance and mentoring
• Inform and maintain best practices for reliability and observability for the team
• Troubleshoot and resolve production issues

Benefits

• Gender-affirming care and support
• Family care and support, including family planning and fertility benefits
• A variety of mental health resources
• Medical, dental, and vision insurance for employees and dependents
• Free meals and refreshments at the office (conversation and community is an added bonus!)
• Paid vacation, sick time, bereavement, and holidays, paid leaves, sabbatical, and more

Bar Raiser: You’ve spent time mentoring and raising the technical bar for the entire organization. Others look to you for guidance on how to tackle ambiguous problems and handle competing prioritiesTechnical Expertise: You are a Ruby and Rails expert. You have navigated massive Rails applications, worked with Ruby across multiple codebases, and are comfortable working at multiple layers of abstractionPlatform Thinker: You’ve designed and built platforms and public-facing APIs, and have a strong understanding of how to build for reliability and performance at scaleExperience: 12+ years of professional software development experience. You have been a technical owner for organization-wide engineering initiatives and have played a role in scaling engineering organizationsEffective Communicator: You think in terms of business priorities and know about how to orient your team around the right technical goals for the business as well as how to convey technical constraints and needs to business leadersPayroll domain experience: Payroll, tax or fintech experience is a real head start. It’s also learnable, and we’ll teach itAgent facing tooling: Experience designing interfaces consumed by a model - MCP servers, tool and function definitions or an integration path for AI providers. We care how you think about turning an API into a navigable tool surfaceGraphQL at scale: You’ve been a client of GraphQL - writing efficient queries, building the query construction and data mapping layer around them, and reasoning about performance when you don’t own the resolvers. You have enough schema fluency to influence the design of APIs other teams own