Java Backend Engineer
Role summary by JobGrid
Java Backend Engineer at LoopMe: Kraków, Poland; Hybrid; Contract; IT; Back End Engineer. JobGrid adds normalized role facts, source context, and a path to the employer application page so candidates can compare the listing before applying.
- Location and workplace: Kraków, Poland, Hybrid
- Role classification: IT, Back End Engineer, Contract
- Source freshness: checked by JobGrid on 2026-05-28.
- Application path: candidates continue to the employer application page with non-personal referral tags.
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