> Markdown version of [/jobs/ext/2158700-software-engineer-core-java](https://www.wearedevelopers.com/jobs/ext/2158700-software-engineer-core-java). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Software Engineer - Core Java - **Company:** Doghouse Recruitment - **Location:** Germany - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Java (Programming Language), Artificial Intelligence, Advanced Message Queuing Protocol, Business Systems, Software Quality, Code Review, Data Integration, Software Debugging, Distributed Systems, Failover, Data Intelligence, Java Persistence API, Junit, PostgreSQL, Microsoft SQL Server, MongoDB, MySQL, Message Queuing Telemetry Transport (MQTT), Oracle (Applications), Performance Tuning, Mockito, TCP/IP, WebSocket, Jetty, Multithreading, Load Balancing, System Availability, Concurrency, Spring-boot, Vert.x, Backend, Apache Kafka, Restful APIs, Grpc, Microservices - **Published:** August 21, 2026 - **Apply:** https://www.jobfinder.de/job/senior-software-engineer-core-java/ ## About the Role ![](https://www.jobfinder.de/wp-content/uploads/2023/11/bax-logo.png) Senior Software Engineer - Core Java - Java 21 monolith - Remote within Germany About the Role Our client is a data integration platform serving more than 2,000 customers, helping them connect business systems, automate workflows, and exchange data across cloud and on-premise environments. Their platform powers supply chains through real-time integration, automation, and intelligent data processing. The codebase is a Java 21 monolith with no microservices and no Spring Boot. The team uses homegrown frameworks built on top of libraries such as Netty, Jetty, and JPA. 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 optimize 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, including the ability to write Java without the Spring Boot framework - 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 monolithic codebase Bonus Skills: Experience in one or more of the following is highly valued and maps to specific 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 optimization - AI focused Tid-1 ## Related Videos - [Inside Bitpanda's Tech Stack: Scaling a European Fintech Leader - Markus Dorner](https://www.wearedevelopers.com/videos/1979-inside-bitpanda-s-tech-stack-scaling-a-european-fintech-leader-markus-dorner) - [How Unit Testing Saved My Career](https://www.wearedevelopers.com/videos/1642-how-unit-testing-saved-my-career) - [MySQL Protocol Features You Should Be Aware Of](https://www.wearedevelopers.com/videos/100267-mysql-protocol-features-you-should-be-aware-of) - [Exploring the Power of gRPC-Gateway for Writing RESTful Services](https://www.wearedevelopers.com/videos/2072-exploring-the-power-of-grpc-gateway-for-writing-restful-services) - [Test-Driven Development: It's easier than you think!](https://www.wearedevelopers.com/videos/1598-test-driven-development-it-s-easier-than-you-think) - [From boy scouting to redrawing the landscape](https://www.wearedevelopers.com/videos/1140-from-boy-scouting-to-redrawing-the-landscape) ## Related Articles - [Find a Developer Job: 12 Best Job Sites For Developers](https://www.wearedevelopers.com/magazine/165-find-a-developer-job-12-best-job-sites-for-developers) - [Is Software Engineering Over-Saturated?](https://www.wearedevelopers.com/magazine/418-is-software-engineering-over-saturated) - [Where To Find Software Engineering Jobs](https://www.wearedevelopers.com/magazine/396-where-to-find-software-engineering-jobs) - [Fully Remote Software Engineer Jobs](https://www.wearedevelopers.com/magazine/447-fully-remote-software-engineer-jobs) - [Finding Jobs in Germany](https://www.wearedevelopers.com/magazine/375-finding-jobs-in-germany) - [How We Built a Worry-Free System That Runs for 10+ Years – And What We’d Do Again](https://www.wearedevelopers.com/magazine/751-how-we-built-a-worry-free-system-that-runs-for-10-years-and-what-we-d-do-again)