Senior Java Backend Engineer — Scalable Data & APIs

SQUARE ONE RESOURCES sp. z o.o. in Warszawa seeks a Senior Java Developer to join a global Risk Technology team responsible for designing, developing, and maintaining high‑performance data processing systems.

You will help deliver strategic technology initiatives and scalable enterprise capabilities. The role demands strong backend Java expertise, multi‑threading and REST API design, and performance tuning, plus collaboration with engineers, architects, and business stakeholders across regions