Senior Software Engineer

Role At Variance, we are teaching machines to make the hardest judgement calls at scale. That means building AI agents for the high-precision gray-area of risk investigations, fraud, and identity reviews. We’re a small, talent-dense team in San Francisco tackling problems that touch billions of events and entities. Our customers include Fortune 500 companies and global marketplaces, and we’re scaling systems that free millions of hours of human effort. We’re looking for a Senior Software Engineer who wants to own product and technical decisions end-to-end. You’ll work directly with the founders to build and scale AI-powered systems where precision, speed, and trust matter deeply. You’re a fit if you: Have 4+ years of professional software engineering experience or equivalent Care deeply about craftsmanship and have strong opinions about product quality, system design, and code quality Thrive in high-ownership environments and want to drive projects end-to-end, from backend architecture to polished UI to production Have strong fundamentals and can ramp quickly in our stack: React/Next.js, TypeScript, MySQL, and ClickHouse Are comfortable making pragmatic technical tradeoffs in ambiguous, fast-moving environments Have experience building reliable systems at scale and debugging issues in production Enjoy collaborating closely with product, design, and leadership to turn fuzzy problems into shipped systems Raise the bar for the team through technical leadership, mentorship, and high standards What you’ll do Own product features and systems end-to-end, from architecture and implementation to launch and iteration Lead technical decisions across the stack, balancing speed, quality, maintainability, and scale Build AI-powered interfaces and decision systems that operate in real time with high precision and user trust Work directly with the founders on frontier problems in fraud, abuse, and risk Scale our product into new industries and workflows through rapid pilots, live demos, and fast feedback loops Improve engineering velocity by shaping internal tools, patterns, and standards Help define the technical foundation of the company as we grow Our culture We believe in ownership, urgency, and craft. We enjoy spirited debate, wild ideas, and building things we're proud of. We're fully in-person in San Francisco. What we offer Competitive salary and meaningful equity Health care: we offer platinum-level medical, dental, and vision insurance Unlimited PTO, sick leave, and parental leave Up to $100 in reimbursement for personal health & wellness expenses each month 401(k) plan