Middle Backend Developer

AIstats is a fast-growing football tech ecosystem built on cutting-edge big data and computer vision. We are a fully remote global team of 30+ people, with a core hub in Warsaw. Backed by Google executives and top mobile founders, we have quadrupled our valuation over the past year. Our mission is to elevate the global football experience: helping fans see the game with greater depth and providing professionals with powerful, next-generation tools to analyze every match.

Responsibilities

• 💡 Development of new HTTP and WebSocket endpoints with integration of third-party APIs (REST/gRPC/GraphQL — depending on tasks)

• Writing unit and integration tests to ensure correct operation of APIs, including boundary cases and work with external services

• Performing load testing and code profiling to identify bottlenecks and improve performance

• Working closely with frontend, analytics and product teams — from discussing specifications to implementing solutions in production

Requirements

Must have:

• Strong knowledge of Node.js and TypeScript, experience in REST/WebSocket API development

• Experience with microservice architecture and interaction between services via RabbitMQ, Redis, TCP connections

• Knowledge of PostgreSQL (query writing, indexing, transactions, migrations)

• Experience with MongoDB and understanding when it is appropriate to use it

• Experience with Docker, understanding of how docker-compose works

• Understanding of the principles of Nginx as a proxy server (including in the context of WebSocket/HTTPS)

• Proficiency with Socket.io, understanding of its features (e.g., rooms, reconnect, persistence, etc.)

• Experience in configuring logging, debugging and profiling backend code </aside>

Nice to Have

• ⭐ Understanding how Billing systems work

• Experience with Elasticsearch: setting up and using it for full-text search

• Load testing skills and tools (e.g. k6, Artillery, autocannon)

• Understanding and implementation of HTTPS, certificates, working via secure WebSocket

• Experience with CI/CD and build automation in a Docker environment

• Team development experience: code review, git flow, Jira/YouTrack/Linear

What We Offer

• 📦 Fully remote work format and flexible working hours

• 💸 Competitive salary pegged to USD

• 🌅 24 days of paid vacation and 15 additional paid days off (including sick leave, personal days and corporate holidays)

• Friendly communication culture, rapid product cycles, and transparent processes

• ⚡ Dynamic work environment with a team passionate about sports and technology

• 🪴 Opportunities for professional development and career growth

• ⭐ No micromanagement — just trust, ownership, and freedom to experiment

• 🎓 Mentorship and high-quality engineering feedback