Frontend Engineer (Contract, Buenos Aires)

Nexus

Location: Buenos Aires, Argentina
Job Type: full-time
Salary: Unknown
Posted: October 30, 2025

Job Description

About Nexus

Nexus is building the foundation for verifiable finance, an economic system where every transaction, order, and settlement can be proven on-chain with cryptographic assurance. To do this we’re developing a DEX Layer 1 blockchain purpose-built for the AI economy, powered by idle compute from millions of people around the world, and verified with zero-knowledge proofs. This is finance rebuilt for the future: verifiable, scalable, and open to all.

Nexus has raised $25M in Series A funding from Lightspeed, Pantera, Dragonfly, SV Angel, and more.

Location: Remote (commutable distance to Buenos Aires)
Type: Contract

Duration: 12 months with potential for extension

The Role

We’re expanding our frontend engineering team in Latin America to build next-generation interfaces for the Nexus ecosystem. As a Frontend Engineer, you’ll design and deliver intuitive, high-performance user experiences for our DEX, developer tools, and verifiable finance applications — making complex financial systems transparent and accessible.

You’ll collaborate with product, backend, and protocol teams in San Francisco while contributing remotely from Argentina or Mexico. We move fast, ship often, and expect engineers to take full ownership of their work.

What You’ll Do

Build responsive, performant web applications in React and TypeScript.
Create interfaces for our enshrined DEX, analytics dashboards, and developer tooling.
Integrate APIs and blockchain services to surface verifiable on-chain data.
Implement interactive visualizations for trades, liquidity, and transaction flows.
Collaborate closely with design to deliver polished, intuitive user experiences.
Iterate quickly based on real-world feedback from traders and developers.

What We’re Looking For

Strong experience building production React/TypeScript applications.
Solid understanding of web performance, state management, and component architecture.
Comfort integrating backend APIs and blockchain or financial data sources.
A sharp eye for UX, interaction design, and visual clarity.
Excellent communication skills in Business English (spoken & written).

Bonus Points For

Experience with financial applications, trading interfaces, or data visualization.
Familiarity with Node.js, Rust, or WebAssembly.
Experience in Web3 or blockchain-based systems.
Background at high-impact startups or fast-paced environments.

Why Join Us

Build the interfaces powering the next generation of verifiable financial systems.
Collaborate with world-class engineers, designers, and researchers across continents.
Help define how users experience an on-chain DEX embedded in a Layer 1.
Thrive in a fast-paced, ambitious environment where ownership drives growth.

🎯 Who is this job for?

This contract role is ideal for a Frontend Engineer with strong React and TypeScript skills, experience in web performance and API integration, and a good eye for UX. Ideal candidates are based near Buenos Aires, speak fluent business English, and are comfortable building interfaces for blockchain or financial applications. Bonus if you’ve worked with Web3, trading UIs, or data visualization in a fast-moving startup.

💬 Potential Interview Questions

What are key performance optimization techniques for React-based financial dashboards?
Use memoization (useMemo, React.memo), virtualized lists, lazy loading, and avoid unnecessary re-renders through effective state management and component splitting.
How do you manage state in complex React applications, especially for trading interfaces?
I use Context API for app-wide state, Zustand or Redux for predictable state flows, and local useState or useReducer for component-level management, prioritizing reactivity and performance.
Describe your experience integrating APIs with blockchain or financial data sources.
I handle REST/GraphQL calls with axios or fetch, manage real-time updates via WebSockets, and normalize data for efficient rendering and user interaction in sensitive UIs.
What strategies do you use to ensure smooth UX when rendering real-time financial data?
Debounce updates, throttle heavy rendering, prioritize visual clarity with intuitive loading states, and maintain component responsiveness with lightweight updates.
How would you build an interactive visualization for liquidity and transaction flows?
I’d use libraries like D3.js or Recharts in React, manage dynamic SVG/Canvas rendering, and ensure performance with minimal re-renders and real-time data binding.
What are common UX pitfalls in trading apps, and how do you avoid them?
Poor feedback loops, cluttered UIs, and latency in critical interactions; I avoid these by emphasizing clarity, testing with real users, and optimizing every interaction for speed and trust.
How do you ensure code quality and maintainability in fast-paced projects?
Enforce consistent linting, use TypeScript for static checks, write unit/component tests with Jest or Testing Library, and maintain clear folder/module structure.
What’s your experience with deploying internationalized or localized web interfaces?
I use libraries like i18next, separate translation logic from components, and support RTL layouts, date/number formatting, and locale-aware currency displays.
Describe a project where you built a responsive and intuitive financial UI.
I built a trading dashboard with React and Tailwind, showing real-time trades and charts, implementing mobile-first design and high accessibility standards.
How would you work with a backend team across time zones to integrate a DEX frontend?
I’d align on API contracts early, use async collaboration tools, mock APIs during development, and conduct regular syncs or async code reviews to stay aligned.

📋 Job Summary

Nexus is hiring a remote Frontend Engineer (Contract, Buenos Aires) to build cutting-edge React/TypeScript interfaces for their blockchain-powered DEX and financial tools. You'll work with high-performance web apps, on-chain data, and interactive visualizations in a fast-paced, global team. This 12-month contract offers the chance to shape the user experience of a next-gen Layer 1 for the AI economy. If you're based in Argentina or Mexico and ready to build in Web3 with top-tier backing, this is your opportunity.