Full Stack Developer

Who We Are Looking For
We are looking for a Full Stack Developer with strong frontend expertise to contribute to the development and scaling of GreyOak’s real-time market intelligence platform.
The role is ideal for someone who is highly hands-on with Next.js, React, TypeScript, APIs, WebSockets, real-time data handling and interactive charts.
You will work closely with our quantitative research and backend teams to convert APIs, live data streams and quantitative outputs into fast, reliable and responsive product experiences.
While the role requires an understanding of backend integration and application architecture, the primary focus will be on building and optimizing data-intensive frontend applications involving live market data, dashboards, charts, filters and multiple real-time data streams.
Why This Role Is Important to Us
GreyOak is building quantitative market intelligence products that process and present large amounts of historical and real-time market data.
As our products expand, application performance, chart responsiveness, WebSocket reliability and efficient frontend state management become increasingly important.
This role will be responsible for strengthening the application layer between our quantitative/backend systems and the end user, ensuring that real-time intelligence can be delivered reliably without unnecessary loading, rerendering or performance degradation.
What You Will Be Responsible For
As a Full Stack Developer, you will:
Design, develop and maintain applications using Next.js, React and TypeScript.
Build responsive and high-performance dashboards for real-time and historical datasets.
Integrate REST APIs and WebSocket-based real-time data streams.
Manage WebSocket connection lifecycle including subscriptions, unsubscriptions, reconnections and error recovery.
Prevent duplicate socket connections, event listeners and unnecessary subscriptions.
Build and optimize interactive financial charts using streaming and historical data.
Manage live candle and price updates efficiently without unnecessarily rerendering or recreating complete charts.
Build complex filters, selectors, indicators and dashboard interactions.
Implement scalable application state management using Zustand or equivalent technologies.
Optimize React components and state updates to prevent unnecessary rerenders.
Improve application performance using caching, lazy loading, memoization, throttling and debouncing where appropriate.
Handle symbol and timeframe switching efficiently across APIs, WebSockets and charts.
Maintain synchronization between historical data and incoming real-time data.
Identify and resolve frontend memory leaks, slow rendering, excessive API calls and browser performance issues.
Implement stable loading, error and reconnecting states.
Integrate authentication, session management and protected routes.
Develop and maintain API integration layers and Next.js server-side functionality where required.
Work closely with backend and quantitative teams on API contracts, schemas and real-time payload structures.
Troubleshoot production issues and perform root-cause analysis.
Participate in code reviews, testing and application architecture discussions.
Maintain clean, reusable and strongly typed code across the application.
What We Value
These skills will help you succeed in this role:
Strong hands-on experience with React and Next.js.
Strong proficiency in JavaScript and TypeScript.
Good understanding of Next.js App Router architecture.
Strong understanding of React hooks, component lifecycle and rendering behaviour.
Practical experience working with WebSockets and/or Server-Sent Events.
Experience building real-time or frequently updating web applications.
Strong REST API integration experience.
Experience with state management tools such as Zustand, Redux or equivalent.
Experience developing data-intensive dashboards.
Hands-on experience with charting or data visualization libraries.
Strong understanding of asynchronous data handling and frontend state synchronization.
Understanding of WebSocket subscription and reconnection patterns.
Experience diagnosing frontend performance issues using browser development and profiling tools.
Good understanding of caching, memoization, throttling, debouncing and lazy loading.
Understanding of server-side and client-side rendering in Next.js.
Experience implementing authentication and secure session/token handling.
Experience with Tailwind CSS or similar modern CSS frameworks.
Familiarity with Git and standard software development workflows.
Strong debugging and problem-solving skills.
Preferred Technical Experience
Experience in fintech, trading, financial markets, analytics or other data-intensive applications.
Experience building financial or candlestick charts.
Experience with TradingView Lightweight Charts, Highcharts, ECharts or similar charting libraries.
Experience handling multiple simultaneous live data streams.
Experience working with high-frequency or frequently updating datasets.
Experience with Zustand.
Experience with TanStack Query.
Experience with TanStack Table.
Experience with Next.js API routes, middleware and server-side application logic.
Familiarity with Node.js.
Understanding of SQL and/or NoSQL databases.
Experience with Vitest, Playwright or similar testing frameworks.
Familiarity with CI/CD pipelines and cloud deployment.
Understanding of logging, monitoring and application observability.
Education & Preferred Qualifications
Bachelor’s degree in Computer Science, Information Technology, Engineering or a related field is preferred.
Approximately 2–5 years of relevant software development experience.
Strong practical experience will be valued over years of experience alone.
Candidates with demonstrated experience building real-time, chart-heavy or data-intensive applications will be preferred.
About GreyOak
GreyOak Capital Intelligence is a fintech company building quantitative market intelligence products designed to make complex market data easier to interpret and use.
Our technology combines proprietary quantitative models, historical and real-time market data and modern product experiences to deliver structured market intelligence across financial markets.
Our platform involves real-time market data, quantitative analytics, interactive charts, multiple timeframes, filters, dashboards and data-driven intelligence.
The technology and quantitative research teams work closely together to transform complex market data and proprietary model outputs into simple, scalable and reliable product experiences.

Work arrangement
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