Front end Engineer [Brazil]

About Arena:

Arena is a startup created in Silicon Valley with a mission to build communities for creators, publishers and brands with the power of AI. Companies using Arena include Disney, Reuters, Fox, Red Bull and NFL. We have +2,000 customers in 150 countries, with +50M users engaging and having conversations on Arena every month.

We are a Series A company backed by top-tier investors such as CRV, Redpoint and Craft Ventures. Arena offers a unique work environment and the chance to collaborate with diverse teammates across multiple countries, with a culture of ownership, autonomy, and high performance.

Arena is expanding its AI product portfolio with MyAvatar.AI, a multimodal platform that enables users to create intelligent, personalized AI avatars through voice, video, and conversational interfaces.

Sometimes you're stuck in a job that doesn't make sense, working with outdated code and a stack that holds you back. If you love a good challenge, enjoy solving meaningful problems, and want to be part of a fast-growing AI startup in Silicon Valley — then Arena is the company you're looking for.

About the Role:

We’re looking for a Frontend Engineer to build fast, scalable, and high-performance web experiences across Arena’s products.

You’ll work closely with Product, Design, and Engineering to build AI-powered features, improve existing applications, and solve complex frontend and performance challenges. You’ll work alongside experienced engineers and have a direct impact on products used by millions of users.

What you will be doing:

Build and maintain high-performance frontend applications using React, Next.js, and TypeScript.

Develop real-time experiences and interfaces using WebSockets and GraphQL.

Build reusable, scalable, and maintainable UI components and frontend architecture.

Integrate frontend applications with APIs, AI services, and backend systems.

Optimize application performance, scalability, and reliability across high-traffic environments.

Collaborate with Product and Design to turn product requirements and UI/UX concepts into polished experiences.

Debug complex frontend and production issues and implement robust solutions.

Contribute to AI-powered features, including conversational experiences and AI Agents.

Must-Have Experience:

3+ years of professional frontend engineering experience.

Strong experience with TypeScript and React.

Production experience with Next.js.

Experience working with GraphQL and REST APIs.

Experience building real-time applications using WebSockets.

Experience with Git and collaborative software development workflows

Experience working in monorepo environments.

Strong problem-solving skills and attention to performance, scalability, and code quality.

Fluent English

Our Stack:

Frontend: React.js, Next.js, TypeScript.

UI: Web Components, CSS, Styled Components.

APIs & Real-Time: GraphQL, REST, WebSockets.

Build & Architecture: Monorepo, Turborepo, Webpack.

Infrastructure & CI/CD: GitHub Actions, Firebase, Firestore.

Design: Figma.

Nice-to-Have Experience:

Styled Components or other CSS-in-JS solutions.

Turborepo, Webpack, or similar frontend tooling.

GitHub Actions and CI/CD workflows.

Node.js and backend development.

Firebase and Firestore.

Experience building browser extensions or WordPress plugins.

Experience with AI-powered products, conversational interfaces, or AI Agents.

Example Projects You’ll Be Working on:

Implement applications using Next.js framework

Build a real-time chat that can scale to 1M simultaneous users

Develop plugins for WordPress and Google Chrome

Implement high-performance widgets

Build a JavaScript SDK

Build and design AI features and AI agents

We also have some sweet perks like:

• 🔥 Be a part of the team in Silicon Valley and join a global team.
• 💪 A team of exceptional engineers leading the cutting-edge AI Agents.
• 💶 Competitive salary package & benefits.
• ⛱️ 4 weeks of paid time-off.
• 📖 Learning and Development budget.
• 🚀 Key moment to join Arena in terms of growth and opportunities.
• 💻 Ability to put your stamp on real-world AI applications that serve millions of users.
• 📚 Fast-learning environment, entrepreneurial and strong team spirit.
• 🌍 Multiple nationalities: cosmopolite & multi-cultural mindset.
• 💆‍♀️ Our people matter, work-life balance is important at Arena.