AI Engineer

About Arena: Arena is 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, growth, and responsibility). We are 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 having conversations on Arena every month and engaging with our AI Agents. Arena is also 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, building AI features that never make it into production. If you enjoy turning cutting-edge AI into real products, solving complex problems, and seeing your work used by millions of users — then Arena is the company you're looking for. About the Role: We’re looking for an AI Engineer to build and scale AI-powered experiences across Arena and MyAvatar.AI. You’ll work closely with Engineering, Product, and other AI-focused teams to design, implement, evaluate, and improve AI systems that power conversational, voice, and multimodal experiences. What you will be doing: • Build and integrate AI-powered features and services into production applications. • Develop LLM-powered applications using APIs, agents, RAG, tool calling, and structured outputs. • Design and improve AI pipelines for conversational, voice, and multimodal experiences. • Evaluate model quality, reliability, latency, and cost, and continuously improve AI performance. • Build experiments and prototypes, then turn successful approaches into scalable production systems. • Collaborate with Product and Engineering to translate business and user problems into practical AI solutions. Must-Have Experience: • 2+ years of experience in AI Engineering, Machine Learning Engineering, Software Engineering, or a similar technical role. • Strong Python programming skills and experience building production software. • Hands-on experience with LLMs, Generative AI, and AI APIs. • Experience building applications with RAG, embeddings, vector databases, agents, or tool calling. • Strong understanding of AI evaluation, prompt engineering, model behavior, and production trade-offs. • Experience working with APIs, cloud infrastructure, and distributed systems. • Strong problem-solving skills and ability to move quickly from prototype to production. • Fluent English. Nice-to-Have Experience: • Experience with LangChain and LangGraph for building LLM applications, agents, and AI workflows. • Experience with Node.js and TypeScript or other backend languages. • Experience with AWS, serverless architectures, and cloud-native applications. • Experience with real-time systems, WebSockets, GraphQL, or APIs. • Experience with MongoDB, PostgreSQL, Redis, or other distributed data systems. 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.