Back End Engineer - Core Java

Senior Software Engineer – Java (Networking Focus)

About the company

A data integration platform provider connecting supply chain partners and systems across formats and technologies, serving thousands of customers across Europe. The platform combines real-time integration, automation, and data quality control to support AI-driven and cross-company data flows.

Role overview

The Engineering department is expanding its data platform, data network, and connected data products. This role sits within backend engineering, focused on network-layer and integration systems, working alongside senior engineers on low-level networking infrastructure, data transport, and platform scalability. The team actively uses AI as a force multiplier, both for coding and for rethinking engineering workflows.

What you'll do

• Develop, test, and deploy core backend components of the data platform, with a focus on performance, reliability, and scalability
• Design and implement network-layer solutions in Java, including HTTP tunnelling, TCP/IP communication, and Netty-based pipeline architectures
• Build and maintain load balancing strategies for distributed, high-availability systems
• Design integrations combining cloud systems with on-premises data sources
• Contribute to technical designs and participate in code reviews
• Integrate AI tools into the engineering workflow to accelerate development, automate repetitive tasks, and improve code quality
• Collaborate with QA and product teams on reliable, high-quality releases

What you bring

• Around 3-6 years of backend development experience with strong hands-on Java skills
• Solid understanding of Java networking internals, including NIO, sockets, HTTP/HTTPS tunnelling, and proxy protocols
• Practical experience with Netty or similar async frameworks (Vert.x, gRPC), with ability to reason about event loops, channel pipelines, and non-blocking I/O
• Knowledge of load balancing concepts: L4/L7, connection pooling, health checks, failover strategies
• Strong debugging skills, particularly with low-level networking or concurrency issues
• Experience with test automation (JUnit, Mockito or similar)
• Hands-on experience with at least one database (PostgreSQL, Oracle, MSSQL, MySQL, or MongoDB)
• Understanding of integration protocols: HTTP/HTTPS, REST, WebSocket, or gRPC
• Confidence with concurrency and multithreading in Java
• Some exposure to asynchronous messaging (Kafka, AMQP, MQTT)
• Proactive attitude toward AI-augmented engineering
• TypeScript familiarity is a plus but not required
• Clear English communication; German is a welcome plus but not required

What's on offer

• 75-95K Euro per year
• Flexible remote work options
• Modern offices in Germany and the Netherlands
• Personal learning and development budget
• Up to 30 days remote work per year from any EU country
• 2 additional paid days off (Christmas Eve, New Year\'s Eve)