Backend Developer

About AIstats
AIstats is transforming the football data market by moving from 2D to 3D, powered by a cutting-edge Computer Vision and Machine Learning ecosystem that unlocks deep insights for both fans and professionals.
In 1.5 years, the Warsaw-based startup has grown from $0 to $3M ARR and secured over $2M in funding. As an AI-first startup, we’re looking for passionate builders who want to create something big and shape the future of football intelligence with us.

What we build
Advanced Football Analytics - a mobile app for football fans and bettors that reached 100k MAU in less than a year, featuring advanced statistics powered by our proprietary ML and Computer Vision technologies.

Advanced Analytics for Football Clubs - a next-generation analytics platform helping football clubs, scouts, and agents make smarter decisions both on the pitch and in the transfer market. Thanks to our early leadership in skeletal tracking data, AIstats secured several Tier-1 club partnerships within months of launching the platform.

Key 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.

Will be a plus:
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)
A 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.

Join our team and help drive innovation in the football industry!