Why This Job is Featured on The SaaS Jobs
This Senior Staff Engineer role sits at the platform layer of a mature SaaS product where payroll tax compliance is a core workflow, not an add-on. Work in this domain tends to be defined by correctness, auditability, and reliability, which makes platform decisions unusually consequential across the wider application. The listing also signals a modern SaaS environment balancing established Ruby and TypeScript stacks with deliberate investment in extensibility and safe use of agentic AI in regulated concepts.
For a long-term SaaS engineering career, the value here is exposure to how foundational services, APIs, and tooling enable multiple product surfaces to move in sync while keeping risk controlled. The remit spans end-to-end project leadership, architectural evolution of existing systems, and operational ownership, all of which translate well to other subscription businesses with high-volume workflows and strict accuracy expectations. Cross-functional partnership with product, compliance, operations, and data functions reflects how SaaS platforms are actually run at scale.
This role tends to fit engineers who enjoy turning ambiguous, high-stakes requirements into clear technical strategy and durable systems. It is also well suited to those who prefer influencing across teams through design reviews, incident learnings, and mentorship, rather than focusing solely on isolated feature delivery.
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 hiring seasoned engineers to join our teams that work on core platform capabilities, improving our existing systems for extensibility and scalability, and building the future of Gusto's Tax platform. As a Gusto Software Engineer at this level, you’ll be guiding projects end-to-end by influencing initial feature specs, understanding how to take existing systems closer to desired end states, executing on projects, and maintaining code that powers core experiences. If you’re interested in building elegant software with far-reaching effects in our modern economy, join us!
About the Team:
Payroll is the beating heart of Gusto’s business. The Tax team ensures Gusto customers remain compliant and confident by managing every aspect of payroll taxes—including setup, calculation, payments, filings, and year-end communications. We design seamless, end-to-end experiences that simplify complex processes and build the infrastructure that keeps taxes accurate and on time. By combining reliable systems with thoughtful design, our team makes one of the most complicated parts of running a business simple for employers. Tax is a stabilizing pace layer at Gusto: continuity and trust are paramount, change is deliberate, and impact is wide. The domain is highly complex and offers the opportunity to engage in system design that simplifies this for customers.
Here’s what you’ll do day-to-day:
- Design, build, and test the platform that supports tax compliance for millions of people
- Help scale one of the largest Ruby/Rails and TypeScript/React applications in the world
- Collaborate on complex and ambiguous problems with partnerships from Engineering, Product Management, Design, Data Science, Compliance, Operations, and other cross-functional teams
- Improve the productivity and happiness of our teams with the services, tools, and APIs you build.
- Build guardrails into the Tax platform that enable Gusto to safely leverage agentic AI to interact with tax concepts in a way that ensures compliance, accuracy, stability, and reliability.
- Engage in a highly supportive environment working with others to drive productivity and innovation
- Own and drive the technical strategy and roadmap for your team’s domain area in alignment with team and group-level OKRs
- Identify and prioritize long-term investments to improve foundational systems and architecture
- Lead improvements to incident response processes, tooling, and culture to enhance system reliability and team effectiveness
- Mentor and develop engineers on your team working to create holistic and scalable solutions. Track record of elevating team capabilities through pairing, code review, and knowledge sharing.
Here’s what we're looking for:
- Successful applicants have at least 10+ years of experience
- Experience in designing and developing robust, distributed systems using multiple general-purpose programming languages
- Experience influencing and guiding the work of multiple teams on scaling, refactoring, and optimizing legacy products
- Experience architecting, building, and testing large-scale production level code
- An aptitude and interest in bringing clarity and simplicity to complex and ambiguous problems
- Ability to communicate technical complexity and help facilitate informed tradeoffs
- Enthusiasm for a highly collaborative, test-driven environment
- Able to build maintainable, structured, well-documented code
- Experience building fault-tolerant, mission-critical software
- Experience building products in highly regulated and high risk domains
- Experience in one of these domains is preferred: Payroll, Taxes, or Compliance
- Familiar with current AI tools (LLMs, Agents) and their shortcomings / benefits
- Embeds AI in daily development workflow (scaffolding tests, summarizing docs) to measurably reduce cycle time.
- Mentors engineers on effective AI usage and helps develop an AI strategy for other engineers
- Bonus: Experience with Ruby on Rails, Typescript, and React
Our cash compensation amount for this role is targeted at $223,000/yr to $278,000/yr for San Francisco. 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.
