Sr. Staff Engineer

Job description

ABOUT POLYMARKET Polymarket is the world's largest prediction market platform. We enable individuals to express views on real-world events by trading on outcomes across politics, economics, sports, culture, and current affairs. Built as a peer-to-peer marketplace with no centralized "house," Polymarket aggregates diverse opinions into transparent, market-based probabilities that reflect collective expectations about the future. We're growing fast, both in terms of volume ($21B traded in 2025) and adoption as an alternative news source. Our ambition is to become a ubiquitous beacon of truth in global media and we need your help adding fuel to the fire. ABOUT THE ROLE The Growth Engineering team owns the systems that determine how people find Polymarket, what they do when they get here, and whether they come back. That means analytics infrastructure, martech integrations, experimentation frameworks, and the full-stack features that move conversion and activation numbers. It's a small, high-output team where the work is technical and the stakes are real. We're hiring a Sr. Staff Engineer to be the technical foundation of that team. You'll own architecture decisions that affect how the entire team measures and ships work. You'll build and maintain the data pipelines that growth depends on, set the standard for how experiments are designed and evaluated, and ship full-stack features end-to-end without waiting on anyone else. This is not a coordination role. You will be writing code daily. This hire matters because growth at Polymarket is accelerating and the infrastructure underneath it needs to scale with it. The person in this role will have direct influence on what gets built, how it gets built, and what gets retired. You'll do that as a senior IC with the trust and autonomy to make high-stakes calls, not someone who needs sign-off at every step. WHAT YOU'LL DO - Build and maintain Go-based data pipelines that power growth analytics, from event ingestion to reliable reporting that the team actually trusts. - Audit existing martech integrations, identify what's underperforming or redundant, and replace or retire tooling with clear-eyed judgment. - Architect and ship experimentation infrastructure that lets the team run clean A/B tests, measure results accurately, and move fast without breaking measurement. - Ship full-stack growth features in Go and TypeScript, owning the work from backend service to frontend implementation without handing off. - Bring ML where it adds real value, including personalization, predictive modeling, and experiment analysis, and build those systems into production, not just prototypes. - Review experiment designs and code from other growth engineers, raising the quality of what ships and how the team thinks about building. - Use AI tools daily and seriously, applying them to accelerate your own output and set a higher bar for how the team works. WHAT WE'RE LOOKING FOR - 10+ years of experience spanning full-stack development, data and analytics infrastructure, and martech systems. - Production-level expertise in Golang and TypeScript. You write both regularly and know where each one has edges. - A track record of designing analytics and data pipelines that teams rely on in production, not side projects or internal dashboards nobody checks. - Hands-on experience building and shipping ML systems. You've taken models past experimentation and into production. - Strong systems thinking and the judgment to make architectural calls between refactor and rewrite, talking through real trade-offs rather than defaulting to a preference. - Fluency with AI-assisted development. You use these tools every day and you're faster and more accurate because of it. - Experience setting technical direction for a growth or data team, with high-stakes calls made under ambiguity and limited oversight. - (Plus) Prior experience on a marketplace, fintech, or consumer product with meaningful user scale. - (Plus) Familiarity with prediction markets, financial products, or real-time data systems. - (Plus) People management experience. You don't need it for this role, but it's useful context. BENEFITS - Competitive salary & equity - Unlimited PTO - Full Health, Vision, & Dental coverage - 401k match - Hardware setup: new MacBook Pro, big display, & accessories