Senior Frontend Engineer - Real-Time Trading UI (React/TS)

High Roller; New York (NY); On-site; USD 180,000 - 240,000; Full time

Benefits offered by this job

Health benefits

401(k) retirement plan with company  匹

Job summary

High Roller seeks a Senior Frontend Engineer in New York to build the customer-facing experience for our prediction markets platform across web and mobile. You will own end-to-end frontends using React, React Native, and TypeScript, delivering real-time interfaces with live data feeds and session management.

You will collaborate with Product, Design, Backend, QA, and Compliance, contribute to the design system, ensure accessibility, and optimize performance for a fast-paced trading product in a

Qualifications

• 5–7 years of professional frontend engineering experience.
• Deep React experience with strong TypeScript and JavaScript skills.
• Experience building complex production web applications.
• Experience with real-time interfaces, WebSockets, or streaming data.
• Implemented authentication in production (OAuth 2.0 / OIDC, token lifecycle, secure sessions).
• Experience building accessible interfaces (WCAG 2.1 AA).
• Strong HTML, CSS, responsive design, and API integration.
• Strong debugging and frontend performance skills.
• Comfortable working with Product, Design, Backend, QA, and Compliance.
• Based in New York and able to work from our New York office.

Responsibilities

• Design and build customer-facing experiences using React, React Native, and TypeScript.
• Develop trading interfaces, live positions, settlement views, wallet and payout flows, identity journeys, and promotions.
• Build real-time interfaces using live data feeds and WebSockets under live market conditions.
• Build sign-up, sign-in, and session flows against Keycloak-based identity platform (OAuth 2.0 / OIDC, PKCE, passkeys).
• Contribute to the shared web and React Native design system.
• Ensure consistent experiences across web and mobile with design tokens and fixed-width live ticking numerals.
• Review partner codebases and maintain frontend architecture with external platforms.
• Build and improve internal back-office tools and dashboards.
• Monitor frontend performance, Core Web Vitals, and native frame times.
• Mentor across the engineering team and support architecture discussions.

Skills

React

TypeScript

JavaScript

HTML/CSS

API integration

WebSockets

Frontend performance

OAuth 2.0 / OIDC

WCAG accessibility

Design systems

Tools

Keycloak

WebAuthn / passkeys

React Native

Sentry / Datadog RUM

Job description

High Roller seeks a Senior Frontend Engineer in New York to build the customer-facing experience for our prediction markets platform across web and mobile. You will own end-to-end frontends using React, React Native, and TypeScript, delivering real-time interfaces with live data feeds and session management.

You will collaborate with Product, Design, Backend, QA, and Compliance, contribute to the design system, ensure accessibility, and optimize performance for a fast-paced trading product in a