Staff Software Engineer, Financial Infrastructure

Gusto•San Francisco, NY

2d•Hybrid

About The Position

You’ll be a key engineer focused on building and owning the systems that move money and assets through Gusto Retirement. This is a very hands-on role: owning backend services and APIs end-to-end, shipping production code, and working through real financial edge cases. You’ll partner closely with product, compliance, and operations to turn complex financial requirements into reliable software. If you like working on core systems where correctness matters and enjoy getting things shipped, you’ll be a great fit. The Financial Infrastructure team owns the core money and asset flow systems for Gusto Retirement. We’re a senior team that works on payments, settlements, tax and compliance integrations, and much more. The work is complex and often cross-functional, so we stay focused, collaborate closely, and keep tight ownership of what we build. We work closely with product and partner teams, but we’re responsible for execution and reliability end-to-end.

Requirements

8+ years of software engineering experience building and shipping production products or platforms
Strong experience with services, APIs, and data-heavy workflows.
Experience working on financial systems, payments, or other high-correctness domains (or the ability to ramp quickly).
Comfortable owning systems end-to-end, including production support and operational work.
Experience working closely with PMs and cross-functional partners to deliver scoped work.
Pragmatic, execution-focused approach to engineering.
Clear communicator and collaborative teammate.
Ability to mentor engineers to maximize their performance and impact
Experience with Ruby on Rails (or a comparable backend framework).

Nice To Haves

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.

Responsibilities

Design, build, and ship services and APIs for money movement and financial integrations
Work on payments, settlements, reconciliation, and corrections involving real customer funds
Build and support critical workflows like payroll integration, KYB/KYC, 401k loans, billing and invoicing, and IRA
Partner with product, compliance, and operations to scope work and deliver production-ready solutions
Debug production issues and improve reliability, observability, and operational tooling
Collaborate with other engineering teams to integrate with shared systems and platforms
Mentor other engineers to help solve some of the hardest technical problems out there in very complex domains and at a large scale
Write clear, reliable, well-tested code that ships quickly and scales well
Build a product that our customers genuinely love