Java User Group Xmas-Edition - JUG x IBM with Talks & Drinks
The JUG Berlin-Brandenburg and IBM are excited to invite you to an inspiring community evening on 2nd December, 2025.
Whether you’re a seasoned Java developer, curious about Java-combined AI, or passionate about modern DevOps & DevSecOps practices, this event will offer valuable insights, practical demos, and plenty of opportunities to connect with like-minded Java tech enthusiasts.
We will have a number of interesting talks across multiple topics, so there should be some inspiration for everyone.
The Talks
Java meets AI – Model Context Protocol (MCP) (Sandra Ahlgrimm)
Let’s learn about the Model Context Protocol (MCP), a cutting-edge framework designed to standardize interactions between AI models and client applications. Through this beginner-friendly session, Sandra will introduce you to MCP and guide you through creating your first MCP server with Langchain4j and Quarkus.
IT Resilience Automation combined with AI-driven DevSecOps (IBM Internal)
Discover how IBM is rethinking the coding lifecycle and DevOps, with tools and approaches designed to streamline workflows, accelerate delivery, and enhance developer productivity.
From Compressed OOPs to Compact Headers – JVM Internals Explained Clearly (Sven Woltmann)
Java 25 introduces a fundamental change to the memory layout of objects: Compact Object Headers. In this talk, you’ll learn – supported by numerous illustrations – what this feature is all about.
We’ll use Compact Object Headers as a starting point to explore the world of object headers, object pointers, and class pointers: What exactly are OOPs (ordinary object pointers), and how do compressed OOPs work on 64-bit systems? How are traditional 128-bit object headers structured – and how can they be reduced to 96 or even 64 bits?
You’ll discover what the Mark Word is, how it’s structured, what role it plays in locking – and how that relates to the pinning of Virtual Threads. We’ll take a look at the evolution from legacy locking to lightweight locking – and how this progression paved the way for header reduction through Project Lilliput.
And last but not least, you’ll find out why smaller objects not only save memory, but can also significantly boost your application’s performance.
This talk is for developers who not only work with Java, but also want to understand the JVM mechanisms under the hood.
Project Bob (IBM Internal)
A short but exciting teaser of what’s coming next in AI-featured IDEs and the vibe coding innovation pipeline.
The Speakers
Sandra Ahlgrimm helps developers build AI-driven Java applications at Microsoft. As a Cloud Advocate, she focuses on making sure engineers can add new capabilities without abandoning their standard workflows and tools.
Before moving into advocacy, she set up automated infrastructure and DevOps pipelines for startups and large enterprises like Axel Springer. Today, her work breaks down practical approaches to applied AI. Her recent talks explore integrating Spring AI and managing prompt testing natively within a codebase.
The Location
The Program
Afterwards, there will be time for networking and a chat.
The Registration
For this event you have to register at via IBM. We look forward to seeing everyone.