Senior Software Engineer, React SDK

About Gusto

At Gusto, we're on a mission to grow the small business economy. We handle the hard stuff—like payroll, health insurance, 401(k)s, and HR—so owners can focus on their craft and customers. With teams in Denver, San Francisco, and New York, we’re proud to support more than 400,000 small businesses across the country, and we’re building a workplace that represents and celebrates the customers we serve. Learn more about our Total Rewards philosophy .

About the Role:

We’re looking for a Senior Frontend Engineer to join the SDK team within Gusto Embedded. You’ll build the reusable frontend foundation that enables partners to run payroll, manage companies, onboard contractors, and power other critical back-office workflows directly on top of Gusto’s platform.

In this role, you’ll design and evolve scalable React + TypeScript components used across multiple areas of the Gusto platform, shaping how partners integrate and build. You’ll own initiatives from technical design through delivery while working closely with backend and partner-facing teams to expand and mature the SDK.

As the platform grows, you’ll tackle complex business logic, localization, accessibility, and long-term architectural sustainability — designing abstractions that are powerful, intuitive, and built to scale. This role is ideal for engineers who are excited by platform work, energized by ambiguity, and motivated by building systems that empower other engineers and partners to move faster.

About the Team:

The React SDK team within Gusto Embedded builds the SDK layer that enables partners to power payroll, company management, contractor workflows, and other core back-office experiences directly on top of Gusto’s platform. We focus on designing reusable interfaces, clear service contracts, and strong developer experience to make integrations reliable and scalable.

As adoption grows, we’re expanding SDK coverage across more areas of the platform while strengthening architectural consistency and long-term stability. You’ll join a small, high-ownership team that values thoughtful abstraction, domain understanding, and building tools that empower other engineers and partners to move faster.

Here’s what you’ll do day-to-day:

• Design and evolve reusable SDK interfaces and components that power payroll, company management, contractor workflows, and other core platform capabilities
• Own technical initiatives from API and abstraction design through production delivery
• Collaborate with backend engineers to define clear, maintainable contracts between platform services and the SDK layer
• Support partner feature development and migrations from legacy integrations to modern SDK interfaces
• Raise SDK quality standards across testing, localization (i18n), accessibility (a11y), and developer experience
• Leverage AI-assisted development tools strategically to accelerate implementation, improve code quality, and explore new ways of building and evolving SDK capabilities

Here’s what we're looking for:

• 5+ years of professional frontend or platform engineering experience, with strong proficiency in React and advanced TypeScript (including API surface and type design)
• Experience building scalable, reusable systems such as SDKs, component libraries, or integration layers
• Strong understanding of frontend–backend integration patterns and experience collaborating on clear service contracts
• Practical experience implementing localization (i18n), accessibility (a11y), and high-quality testing standards
• Ability to operate effectively in evolving systems and make thoughtful abstraction decisions under ambiguity
• Experience in payroll, HR tech, fintech, or other complex back-office domains is a strong plus
• Familiarity with AI-assisted development tools and interest in applying them strategically to improve engineering workflows

Our cash compensation amount for this role is targeted at $140,000-$170,000/year in Denver, $160,000-$185,000/year in Los Angeles, and $170,000-$210,000/year for San Francisco, New York, and Seattle. Final offer amounts are determined by multiple factors including candidate experience and expertise and may vary from the amounts listed above.

Gusto has physical office spaces in Denver, San Francisco, and New York City. Employees who are based in those locations will be expected to work from the office on designated days approximately 2-3 days per week (or more depending on role). The same office expectations apply to all Symmetry roles, Gusto's subsidiary, whose physical office is in Scottsdale.

Note: The San Francisco office expectations encompass both the San Francisco and San Jose metro areas.

When approved to work from a location other than a Gusto office, a secure, reliable, and consistent internet connection is required. This includes non-office days for hybrid employees.

Our customers come from all walks of life and so do we. We hire great people from a wide variety of backgrounds, not just because it's the right thing to do, but because it makes our company stronger. If you share our values and our enthusiasm for small businesses, you will find a home at Gusto.

Gusto is proud to be an equal opportunity employer. We do not discriminate in hiring or any employment decision based on race, color, religion, national origin, age, sex (including pregnancy, childbirth, or related medical conditions), marital status, ancestry, physical or mental disability, genetic information, veteran status, gender identity or expression, sexual orientation, or other applicable legally protected characteristic. Gusto considers qualified applicants with criminal histories, consistent with applicable federal, state and local law. Gusto is also committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. We want to see our candidates perform to the best of their ability. If you require a medical or religious accommodation at any time throughout your candidate journey, please fill out this form and a member of our team will get in touch with you.

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