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High Roller

Senior Frontend Engineer

New York, NY

Full-time

$180,000 to $240,000 a year

About the job

ROLR is building a prediction markets platform delivering the frontier of trading on sports, culture, economics, AI, commodities, and geopolitics. You'll be on a nimble startup-like team within a public company. Our customer experience spans mobile and web, from markets and live trading interfaces to onboarding, identity, payments, and operational tools. Our differentiation lives before the cashier: the game, the graph, and the notification. The consumer surface is the asset we own outright under every scenario, and this seat builds it. We're looking for a Senior Frontend Engineer to join our team in New York and build the customer-facing experience of our prediction markets platform across web and mobile. You'll work across React, NextJS, React Native, and TypeScript, building complex real-time consumer experiences with significant ownership from idea through production. This is not a role for someone who implements tickets. We're looking for engineers who think like product builders. Key Responsibilities: • Design and build customer-facing experiences using React, NextJS, React Native, and TypeScript • Develop trading interfaces, live positions, settlement views, wallet and payout flows, identity and verification journeys, and promotions • Build real-time interfaces using live data feeds and WebSockets that stay honest under live market conditions • Build sign-up, sign-in, and session flows against our Keycloak-standardized identity platform: OAuth 2.0 / OIDC with PKCE, token lifecycle, passkeys (WebAuthn), and biometric step-up on native surfaces • Develop and contribute to the shared web and React Native design system: one component API, two renderers • Ensure consistent experiences across web and mobile: design tokens, 44pt touch targets, live-ticking numerals in fixed-width slots • Work directly across internal and partner-maintained frontend codebases, and review partner work to your own standard • Maintain strong frontend architecture and appropriate boundaries between ROLR and external platform providers • Develop and grow the BFF layer, to support native and web applications • Build and improve internal back-office tools and operational dashboards • Monitor and improve frontend performance: Core Web Vitals on web, cold start and frame time on native • Support code reviews, architecture discussions, and mentoring across the engineering team

You’ll need to: • Have 5+ years of professional frontend engineering experience • Have deep React/NextJS experience and strong TypeScript and JavaScript skills • Be comfortable with backend code, working with a BFF & with backend teams to shape frontend • Have experience building complex production web applications that operate at scale • Have experience with real-time interfaces, WebSockets, or streaming data • Have implemented authentication in production: OAuth 2.0 / OIDC flows, token lifecycle, and secure session handling • Have experience building accessible interfaces (WCAG 2.1 AA) • Have strong HTML, CSS, responsive design, and API integration experience • Have strong debugging and frontend performance skills • Be comfortable working across Product, Design, Backend, QA, and Compliance • Be based in New York and work out of our New York office Preferred Experience • React Native in production (strongly preferred: our flagship surface is native mobile) • Design systems, tokens, theming, and component libraries • Keycloak or comparable identity platforms, passkeys / WebAuthn, biometric unlock • Real-time market data or trading interfaces • Fintech, trading, prediction markets, or another regulated industry • Internal/admin tooling frameworks and frontend observability (Sentry, Datadog RUM) • Experience with experimentation and A/B testing, using data and insights to inform product decisions and continuously improve user experiences. • AI-native engineering workflows: agentic coding, AI-assisted testing and review. Assume a generous token budget; judgment, architecture, and ownership remain the differentiators Compensation Base salary: $180,000–$240,000 per year, based on experience. What We Offer • Competitive health and welfare benefits • 401(k) retirement plan with company match • Flexible vacation policy • Home office setup reimbursement • Access to mental health support