Senior Software Engineer - Tax Calculation

About Rippling
Rippling gives businesses one place to run HR, IT, and Finance. It brings together all of the workforce systems that are normally scattered across a company, like payroll, expenses, benefits, and computers. For the first time ever, you can manage and automate every part of the employee lifecycle in a single system.
Take onboarding, for example. With Rippling, you can hire a new employee anywhere in the world and set up their payroll, corporate card, computer, benefits, and even third-party apps like Slack and Microsoft 365—all within 90 seconds.
Based in San Francisco, CA, Rippling has raised $1. 8B+ from the world’s top investors—including Kleiner Perkins, Founders Fund, Sequoia, Greenoaks, and Bedrock—and was named one of America's best startup employers by Forbes.
We prioritize candidate safety. Please be aware that all official communication will only be sent from @ Rippling.com addresses.

About the Team

Rippling's Tax Platform is one of only ~5 companies globally that owns the full tax calculation and filing stack. We process over $30 billion in annual payroll for 1 million+ employees—growing 50% year-over-year. Our systems handle millions of payroll transactions across multiple countries, ensuring tax correctness across 4,000+ jurisdictions while staying compliant with constantly changing tax regulations.
We're looking for a Senior Software Engineer who takes ownership of complex problems, designs robust systems, and delivers high-quality solutions that directly impact millions of tax calculations.

Why This Role
Rare Opportunity
You'd be joining one of only ~5 companies in the world that owns the full tax stack. ADP took 70+ years, Paychex 50+ years, Paycom 25+ years—Rippling built it in 10. Everyone else licenses from vendors. At Rippling, you own the engine.
Uniquely Hard Technical Challenges
Real-time at scale : Sub-second tax calculations for payroll preview, batch processing of millions of records at month-end, with perfect consistency across retries
Integration complexity : Filing to thousands of agencies via PDF, XML, fixed-width files, SFTP, web portals, APIs—and yes, some still require paper mail
Testing without ground truth : No "tax oracle" exists; you'll build validation systems for millions of edge cases across 50 states × 12 months × multiple entity types
Historical accuracy : Must calculate taxes using rules from any past date as regulations constantly change
The Big Bets You'll Contribute To
Building an AI-Driven Global Tax Engine with explainable AI for full audit defensibility
Massive System Scaling to support 100x current volume and enterprise-grade companies
Expanding International Support to 20+ countries, each with unique tax systems
Building Distributed Transactional Systems handling $100B+ in tax payments
Automating Tax Filing to minimize manual intervention at scale
What You'll Build
FQL (Filing Query Language) : Our proprietary DSL encoding tax rules across 4,000+ jurisdictions
Real-time Tax Calculation : Sub-second calculations at scale with perfect consistency
AI-Powered Compliance Engine : Multi-model validation with human-in-the-loop

What You Will Do
System Design : Architect scalable, reliable systems that handle billions of dollars in tax calculations with zero tolerance for error
Ownership & Impact : Own features end-to-end—from design through production—with direct visibility into business outcomes
Engineering Excellence : Set the bar for code quality, testing practices, and technical documentation within your team
Reliability & Correctness : Build systems where accuracy is non-negotiable; a single bug can mean compliance failures across thousands of companies
Global Scale : Solve challenges unique to processing millions of payroll transactions across multiple countries with 4,000+ jurisdictions and evolving regulations
Collaboration : Partner with compliance, product, and platform teams to translate complex tax requirements into elegant technical solutions
What You Will Have
5+ years of software engineering experience
Strong system design skills with experience building distributed, high-reliability systems
Proficiency in Python; experience with Django or similar frameworks that follow the MVC pattern (layered architecture).
Track record of owning and delivering impactful projects autonomously
Rigorous approach to correctness—you write tests, handle edge cases, and think about failure modes
Ability to navigate ambiguity and drive clarity in complex problem spaces
Clear communication and ability to influence technical decisions
Nice to Have
Experience in fintech, payroll, or tax domains
Background in compliance-critical systems where correctness is paramount
Experience with domain-specific languages or rule engines
Familiarity with MongoDB, Temporal, or event-driven architectures
Tech Stack
Languages : Python, FQL (proprietary tax DSL), Go
Framework : Django, MongoEngine
Database : MongoDB, Redis, PostGre
Infrastructure : AWS, Kubernetes, Temporal
Observability : Buildkite, Datadog, Sentry