Back end Engineer [Brazil]
Remote (Brazil) backend engineer at Arena, a Silicon Valley AI startup building real-time community/chat and AI-agent products for major brands. Day to day: scale WebSockets and APIs to hundreds of thousands of concurrent users and ship AI agent/RAG features, mainly with Node.js/TypeScript, some Go, and AWS, MongoDB, PostgreSQL and Redis.
- Compensation
- Not disclosed
- Location
- Brazil Remote
- Work setup
- Remote
- Seniority
- Not specified
- Employment
- Not specified
- Experience
- 3+ years
- Category
- Backend
- Posted
Skills
Must have
- 3+ years as a backend developer
- Experience with high-traffic and high-performance applications
- Curious developer who experiments with AI and AI agents everyday
- TypeScript
- Node.js
- TDD, BDD, or ATDD
- REST APIs
- MongoDB, AWS DocumentDB, or other document database
Nice to have
- Experience with statically typed languages (e.g. Java, C#, Go)
- Object-oriented and functional programming
- Golang
- AWS
- SQL
- React
Full description
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 and with +50M users having conversations on Arena per month and engaging with our Agent AI.
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. Refactoring code from ages ago, the stack is miles away from what it's supposed to be. If you love a good challenge, enjoy solving meaningful problems, and want to be a part of one of the fastest-growing AI startups in the Silicon Valley — then Arena is the company you're looking for.
What you will be doing:
Our team is made up of very experienced engineers, some with more than 10 years of experience. You will have an enormous impact on making our app and API service faster, more scalable and more flexible. You will collaborate with product and engineering teams to ship AI-powered features and make the existing ones perform orders of magnitude faster.
The challenges:
- Real-time messaging to support 500,000 concurrent users per customer application;
- High performance: our API responses are in the 10ms range;
- Design and build AI Agents, RAG pipelines, model fine-tuning and crawling.
- High scalability: we use sharding, master-master, and master-slave to ensure scalability;
- High availability: our code is running on homepages of the most visited websites and apps on the internet;
- Distributed databases for our Data Platform storing every user engagement.
Our Stack:
- Node.js, TypeScript;
- Golang;
- Websocket;
- Apollo GraphQL;
- AWS Lambda/Serverless framework;
- AWS (API Gateway, S3, VPC, IAM, Fargate, EC2, ALB, CloudFront, Kinesis, SQS, CloudWatch);
- Google Firestore/Firebase;
- MongoDB, PostgreSQL, DynamoDB;
- Redis;
- Cloudflare;