Senior Java Software Engineer

Doghouse Recruitment; Deutschland; Remote; EUR 90,000 - 120,000; Full time

Job summary

Doghouse Recruitment seeks a Senior Software Engineer to join our client’s backend team focused on core Java, concurrency, and scalable platform components. You’ll design, implement, test and maintain production-grade services, collaborating with product, QA and other engineers to deliver reliable releases.

You'll work with databases like PostgreSQL and MongoDB, participate in design discussions, and explore AI-assisted tooling to boost productivity and code quality.

Qualifications

• 5+ years of backend Java development.
• Strong Core Java skills and multithreading experience.
• Experience with PostgreSQL, MongoDB, or similar databases.
• Familiarity with testing frameworks like JUnit/Mockito.

Responsibilities

• Design, develop, test and maintain production-grade backend software in Java.
• Build reliable, scalable platform capabilities and services.
• Contribute to technical design discussions and code reviews.
• Debug and optimize complex production systems.

Skills

Core Java

Concurrency/Multithreading

JUnit/Mockito

SQL & NoSQL Databases

Code Reviews & Collaboration

Job description

Senior Software Engineer – Core Java – (Remote within Germany/Netherlands)

About The Role

Our client is a data integration platform that helps more than 2,000 customers connect business systems, automate workflows, and exchange data across cloud and on-premise environments. Thier platform powers supply chains through real-time integration, automation and intelligent data processing.

The platform powers complex enterprise integrations across on-premise environments first and cloud second.

Depending on your background and interests, you'll join one of several backend teams focused on:

• Core Platform & Data Integration
• Platform & Networking
• API & Backend Services

What You’ll Do

• Design, develop, test and maintain production-grade backend software in Java.
• Build reliable, scalable and maintainable platform capabilities.
• Contribute to technical design discussions and code reviews.
• Debug and optimise complex production systems.
• Collaborate closely with Product, QA and fellow engineers to deliver high-quality releases.
• Use AI-assisted engineering tools to improve productivity, automate repetitive work and enhance software quality.
• Take ownership of features from implementation through production.

What We’re Looking For

• 5+ years of backend Java development.
• Strong Core Java skills.
• Experience with concurrency and multithreading.
• Experience with JUnit, Mockito or similar testing frameworks.
• Experience with PostgreSQL, Oracle, MySQL, SQL Server or MongoDB.
• Comfortable working in a large, long-lived codebase.

Experience in one or more of the following is highly valued, there are 3 teams:

• Networking: Netty, Java NIO, sockets, TCP/IP, HTTP/HTTPS, gRPC, Vert.x
• Distributed Systems: Kafka, AMQP, MQTT, REST, WebSocket
• Platform Engineering: High availability, load balancing, connection pooling, failover, performance optimisation

Nice to Have

• TypeScript or frontend experience.
• Experience with enterprise integration platforms.
• Comfortable using AI-assisted engineering tools such as ChatGPT, Claude, GitHub Copilot or Cursor.