Front-End Developer (Full-Time, Remote)

Headquarters: Remote
URL: https://www.horizonassetinvestments.com/


Front-End Developer (Full-Time, Remote)
 
We are seeking a Front-End Developer to design and build the user-facing components of our high-performance trading platform. You will play a key role in creating intuitive, data-rich interfaces that enable traders and analysts to work efficiently and effectively.
 
You will collaborate closely with the Back-End Development Team and the Project Manager to deliver seamless, integrated systems. A key factor is the front end developer’s ability to deeply discuss approaches, trade-offs, limitations, and pros/cons with the development team, rather than reliance on any specific pattern or library.

 
Key Responsibilities

Develop and maintain the front-end applications of our trading platform.
Collaborate with back-end developers and the project manager to ensure smooth integration across systems.
Design and implement multi-page layouts, menus, and workflows that balance usability with efficiency.
Contribute to the design and user experience of the trading platform, performance & risk manager, and backtesting engine.
Implement and optimize charting and data visualization features, leveraging libraries such as TradingView or D3.js to support a wide variety of chart types (tables, multi-line chart packs, etc.).
Continuously refine the UI/UX to ensure clarity, speed, and intuitive navigation for end users.


 
Qualifications

Strong communication skills and the ability to collaborate effectively with developers, project managers, and business stakeholders.
A keen eye for design, simplicity, and efficiency, with the ability to translate complex requirements into clean, user-friendly interfaces.
Knowledge of financial systems or trading concepts is preferred.

 
Core stack (mandatory)

React 18 + Next.js (App Router), TypeScript, TailwindCSS.
Strong command of state management for high-frequency data (e.g., Zustand, Redux Toolkit, useSyncExternalStore).

 
Real-time data & performance

Hands-on with WebSockets / SSE and reconnection/backoff strategies; handling authenticated socket connections and topic resubscriptions.
Experience implementing backpressure, buffering, coalescing, and windowing to prevent UI thrash under thousands of updates/minute.
Data virtualization (react-virtualized, react-window) for large tables (orders, positions, trades).
Familiar with Web Workers / OffscreenCanvas and message passing to keep the main thread responsive.
Awareness of latency budgets and frame-time profiling using React DevTools and browser performance tools.

 
Charting & visualization

Practical experience with professional charting libs (e.g., TradingView Charting Library, Lightweight Charts, Highcharts, D3).
Real-time overlays: best bid/ask, order book depth, last OHLCV, order/position annotations.
Multi-pane layouts (price, volume, indicators) with synchronized crosshairs and time scales.

 
Architecture & data access

Client-side caching and invalidation (e.g., TanStack Query / React Query).
Schema-driven UI for instruments and venues.
Use of Error Boundaries, Suspense, and progressive hydration/streaming for large Next.js pages.

 
Auth, security, and roles

Strong understanding of OIDC/JWT flows, token refresh/rotation, and WebSocket authentication.
Role-based feature gating (read-only vs trading permissions).

Testing, quality, and reliability

Unit tests for critical transforms/parsers (e.g., Playwright/Vitest for E2E/interaction flows)
Experience with feature flags, staged rollouts, and monitoring with Sentry/OpenTelemetry.

 
Nice-to-haves

Experience with desktop-class layouts (drag-to-dock panels, resizable grids).
Exposure to WASM for heavy computations (e.g., indicator calculations).
Familiarity with FIX/crypto venue nuances (tick sizes, lot sizes, trading sessions).

 
Screening QuestionsKeep answers **4–8 sentences** each. Bullet points allowed if clear.
 
1) **UI migration (hrzk → Next.js):** 
Pick ONE area from the provided `hrzk.html` (e.g., Orders+Trades, Positions table, Equity/Drawdown). 
Explain how you’d migrate it to **React 18 + Next.js (App Router) + TypeScript + Tailwind**. 
Include folder structure and what you’d make **client vs server components**. 
(We care about your trade-offs, not “the one true way”.)
 
2) **Real-time data ingestion:** 
Describe how you’d handle **WebSockets/SSE** for high-frequency updates: 
reconnect/backoff, authenticated sockets, and topic resubscriptions. 
What failures do you expect in production?
 
3) **Backpressure + UI thrash prevention:** 
Assume **thousands of updates/minute** for orders/positions/trades. 
Explain how you’d implement buffering/coalescing/windowing so the UI stays responsive. 
Mention how you’d combine this with **state management** (e.g., Zustand/RTK/useSyncExternalStore) and **virtualization** (react-window / react-virtualized). 
What would you measure to prove it works?
 
4) **Charting approach:** 
We need fast, readable, data-rich charts (equity/drawdown, doughnut/bars, etc.). 
Pick a chart type from `hrzk.html` and explain: 
- which charting library you’d choose (TradingView Lightweight Charts / Highcharts / D3 / etc.) 
- update frequency strategy 
- performance risks + mitigations
 
5) **Auth + role gating:** 
Explain how you’d handle JWT/OIDC token refresh and **WebSocket authentication**, then implement role-based gating (read-only vs trading). 
Use an example like “Cancel All Orders” or “Stop/Start Execution”: when do you hide vs disable vs show a warning?
 
6) **Remote ownership + teamwork:** 
Give one example where you took ownership remotely on an ambiguous task. 
Then describe how you’d work with a small dev team: how you ask clarifying questions, communicate risk early, and avoid shipping “local optimum” code that breaks other parts of the system.
 
What to expect (our interview process):
 
Our hiring process is mostly async and focused on real work.You’ll start with a CV submission and a short, structured application.Shortlisted candidates complete an async technical screen.Finalists complete a paid, time‑boxed work sample aligned to the role.End‑to‑end, the process typically runs 4–6 weeks.
 
FAQs
·       Do I need to respond to the questions?
Yes, please respond to the questions ideally in an open format via a cover letter. This is mandatory for vetting.
·       Do I need to attend live interviews?Most stages are async to reduce scheduling friction. Live calls are minimal.
·       Do I need to be on camera for the sample work?No — screen + voice is sufficient.
·       What tools can I use to submit recordings?Any common screen‑recording or file‑sharing tool is fine, as long as the video is easy to view.
·       Is the final task paid?Yes. Final shortlisted candidates complete a paid, time‑boxed work sample.

To apply: https://weworkremotely.com/remote-jobs/horizon-assset-investments-front-end-developer-full-time-remote