Java Backend Engineer

LoopMe

LoopMe

Software Engineering

Kraków, Poland

Posted on May 22, 2026


We’re looking for a Java Backend Engineer to join LoopMe — a global AI-powered ad tech company redefining how brands connect with consumers across the open internet.

In this role, you’ll help build and scale our Data Management Platform (DMP) — a massively distributed, high-throughput system processing billions of events daily, creating rich device and audience profiles, and exporting data segments to 50+ global partners and exchanges in real time.

You’ll work on complex backend challenges around performance, scalability, data pipelines, and real-time processing, helping power the infrastructure behind large-scale advertising auctions and audience targeting.

This is an opportunity to work on truly high-load systems, collaborate with experienced engineers, and have direct impact on a product used by some of the biggest players in the ad tech ecosystem.

What you'll be doing:

  • Developing features and optimizing performance for large-scale data pipelines (Spark jobs, HBase, Kafka)
  • Designing and optimizing data schemas for relational and NoSQL databases
  • Building microservice applications

Core qualifications:

  • 2+ years of engineering experience
  • Proficiency in Java with a strong understanding of concurrency and distributed systems
  • Experience with Spring Framework or similar IoC frameworks
  • Experience with JPA or other ORM frameworks
  • Strong knowledge of SQL and experience with modern RDBMS (PostgreSQL)
  • Self-motivated, reliable, and comfortable working across a large multi-module codebase

Additional experience we’d value:

  • Experience with Apache Spark or other large-scale data processing frameworks
  • Experience with HBase or other NoSQL/columnar stores
  • Experience with Kubernetes
  • Experience with Kafka
  • Experience with AI/LLM integrations in backend services

Benefits

  • Flexible working schedule with a hybrid type of work
  • Annual performance bonus
  • One month of workation (you can work from any part of the world for one month)
  • Multikafeteria