Staff Fullstack Engineer

Department: Engineering

Location: New York

Employment Type: FullTime

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

We're building a dedicated growth engineering function at the org level, and this role sits at the center of it. Your mandate is user growth: owning the new user experience from first touch to first trade, reducing friction in the acquisition funnel, and building the surfaces that turn curious visitors into active traders. This is not a siloed frontend or backend job — you will work across the entire stack and cut into whatever territory needs cutting into.

The team operates with a mission-driven structure. You will collaborate closely with product, data, and other engineering teams, but you are expected to drive, not wait. Growth at Polymarket is not a marketing problem — it is an engineering problem. The onboarding flow, the KYC experience, the ad-driven funnels that bring people from a sports broadcast into a live prediction market: all of it gets built here.

What You'll Do

• Own and iterate on the new user onboarding flow, from account creation through KYC completion, with a focus on activation rates and drop-off reduction

• Build ad-driven funnel surfaces that route users from external campaigns directly into relevant market pages, coordinating with product on targeting logic and layout

• Ship fullstack features end to end — writing frontend UI, backend services, and third-party integrations — without needing work parceled out across teams

• Identify friction points in the user acquisition funnel using product analytics and experiment your way to solutions, measuring impact at each step

• Review code and make architectural decisions within your domain without waiting for senior sign-off or a fully specced ticket

• Coordinate across engineering teams to get changes made in services you do not own, aligning stakeholders and keeping things moving

• Raise the technical bar on the growth team through code review, direct feedback, and helping less senior engineers scope and ship better work

What We're Looking For

• 7+ years of fullstack engineering experience, with real depth on both the frontend and backend — not just familiarity with one side

• Proven track record shipping user onboarding flows, KYC integrations, or acquisition funnel features, with measurable results you can speak to

• Experience working across teams in a larger engineering org, navigating ownership boundaries and getting things done without top-down coordination

• Strong product instincts — you can look at a funnel, identify what is broken, and propose a fix without waiting for a product manager to hand you a spec

• Comfortable making technical tradeoffs at the system level, scoping across frontend, backend, and external services and choosing the right approach for the constraint

• Clear communicator who can align engineers, product managers, and stakeholders on scope and priorities without creating unnecessary process

• (Plus) Experience with Web3 onboarding flows or crypto-native KYC and compliance tooling

• (Plus) Familiarity with prediction markets, financial platforms, or other high-stakes transaction products

• (Plus) Experience running growth experiments with A/B testing frameworks and interpreting results to drive next steps

Benefits

• Competitive salary & equity

• Unlimited PTO

• Full Health, Vision, & Dental coverage

• 401k match

• Hardware setup: new MacBook Pro, big display, & accessories