Frontend Engineer

Fullstack; New York, Northern (NY, KY); Hybrid; USD 100,000 - 160,000; Full time

Job summary

Fullstack is seeking a Frontend Engineer to build and scale the core user experience of a fast, clear retail trading platform. You will own major frontend systems from architecture to performance, turning complex real-time market data into intuitive interfaces for traders.

You will design reusable UI libraries, develop high-performance visualizations, and work with designers and backend engineers to ship rapidly. In-person collaboration in the United States is expected.

Qualifications

• 2+ years of professional frontend experience.
• Expert proficiency in TypeScript, JavaScript and React.
• Strong UI sense with CSS and WAAPI experience.
• Performance-minded with browser rendering and profiling tools.
• Experience with testing using Jest, Vitest or Cypress.
• Familiarity with REST APIs, WebSocket streams and CI/CD pipelines.
• Able to collaborate closely with in-person teams in the US.

Responsibilities

• Build and scale core frontend systems end-to-end.
• Develop high-performance charts and real-time visualizations.
• Optimize speed and reliability with caching and perf tuning.
• Integrate REST APIs and WebSocket streams into UI.
• Configure CI/CD pipelines for automated builds and rollbacks.

Skills

TypeScript

JavaScript

React

CSS

WAAPI

REST APIs

WebSocket

Lighthouse

Chrome DevTools

Jest

Vitest

Cypress

CI/CD

Performance profiling

Tools

Jest

Vitest

Cypress

Lighthouse

Chrome DevTools

Job description

The Role

As a Frontend Engineer at Fullstack, you will build and scale the core user experience for a retail trading platform designed for speed, clarity, and trust. You will own major frontend systems end to end, from architecture to performance, translating complex real time market data into interfaces that feel intuitive and empowering for everyday traders. You will work closely with designers and backend engineers to ship frequently, refine relentlessly, and deliver a trading experience for fast moving markets.

What You’ll Build & Solve

Core Interfaces: Design, build, and maintain full-featured web applications and reusable UI libraries that are fast, accessible, and scalable.

Data Visualization: Develop high-performance, interactive charts and real-time visualizations that help users make informed trading decisions.

Performance Engineering: Optimize application speed and reliability using advanced caching strategies to achieve sub-second load times.

System Architecture: Integrate complex REST APIs and WebSocket streams while managing robust client-side cached state.

DevOps & Quality: Configure and maintain CI/CD pipelines for automated builds, previews, testing, and seamless rollbacks.

What You Bring

Experience: 2+ years of professional experience building modern frontend applications.

Tech Stack: Expert proficiency in TypeScript, JavaScript, and React.

Design Sensibility: You are obsessed with user interaction and care deeply about the UI. You have an innate sense for making the complex feel intuitive, and have strong experience in CSS and WAAPI.

Performance Mindset: Deep understanding of browser rendering, the DOM, and performance profiling tools (e.g., Lighthouse, Chrome DevTools).

Testing Culture: Experience writing maintainable test suites using tools like Jest, Vitest, or Cypress.

In-Person Collaborator: Thrive in high-bandwidth, in-person engineering environments.

Work Authorization: Must be authorized to work in the United States.