April 28, 2026

Middle/Senior Backend Engineer (Kafka, Java, ELK)

Senior • Remote

4,000 - 4,875 USD

Krakow, Poland

#4928

We are looking for an experienced Backend Engineer to join a well-established development team working on large-scale event-driven systems.

Our client is an integrated shipping services company that has established itself as an independent carrier with a fresh and innovative approach to global logistics. The company operates a smart and efficient worldwide network, delivering reliable shipping services and ensuring stable operations for customers across the globe.

In this role, you will design and build event-driven solutions using Kafka and related technologies, focusing on stream processing applications, data pipelines, and monitoring solutions built with the ELK stack.

Responsibilities:

  • Design and develop event-driven architectures using Apache Kafka and Kafka Streams;

  • Build and maintain stream processing applications and data pipelines;

  • Design and implement ELK pipelines, indexes, dashboards, and alerts;

  • Lead architecture discussions and contribute to the design of Kafka-based event streaming systems;

  • Configure Kafka connectors and manage Kafka topics;

  • Develop scalable event-based processing applications according to architecture and design specifications;

  • Support development and QA teams throughout the software development lifecycle;

  • Contribute to monitoring, observability, and reliability of streaming platforms.

Requirements:

  • 4+ years of experience building Kafka-based applications;

    • Strong experience with Kafka ecosystem components:

    • Kafka Streams (including Processor API)

    • Kafka Connect

    • Schema Registry

  • 4+ years of experience with Java and Spring, implementing Kafka Streams applications;

  • Hands-on experience with the ELK stack (Elasticsearch, Logstash, Kibana) for monitoring and observability;

  • Experience with Logstash Configuration Language (LCL) for configuring pipelines (inputs, filters, outputs);

  • Solid knowledge of SQL and Oracle PL/SQL, including query optimization;

  • Experience working with REST APIs;

  • Experience using Kafka CLI tools and REST APIs for managing Kafka resources;

  • Experience working in Linux/Unix environments;

  • Experience with IntelliJ IDEA;

  • Experience contributing to DevOps processes for Kafka and ELK.

Nice to Have:

  • Experience managing and maintaining ELK servers;

  • Experience with Confluent Kafka Cloud;

  • Experience with Python;

  • Exposure to AI/ML-related projects.

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