Amsterdam Java User Group

Amsterdam JUG Meetup at Just Eat Takeaway.com

02 jun 2026 18:00 CEST

JustEatTakeaway, Piet Heinkade 61, 1019 GM, Amsterdam, NL

Join in with the latest Amsterdam JUG Meetup with the GIGABITES Community at Just Eat Takeaway.com (JET), at Piet Heinkade 61, 1019 GM, Amsterdam.

Note: Our theme for this meetup is Apache Flink. We have two great talks with excellent speakers and we have a third slot, a bit shorter, for anyone who wants to fill it. Do you have experiences with Apache Flink you'd like to share? Write to amsterdamjug@googlegroups.com and you'll get a short slot of 30 minutes, or less, depending on how many sign up!

Agenda

18:00 - Doors Open (And Food!), thanks JET!
18:30 - 19:15 Talk 1: The JET Journey with Apache Flink - Behrooz Mirzaie (Tech Lead at JET)
19:15 - 19:30 Short Break
19:30 - 20:15 Talk 2: From Tables to Streams: Apache Flink for SQL Developers - Viktor Gamov (Principal Developer Advocate at Confluent)
20:15 - 20:30 Short Break
20:30 - 21:00 Placeholder For Your Talk! (See Below)
21:00 The End

Abstracts

Talk 1: The JET Journey with Apache Flink - Behrooz Mirzaie

Our journey with Apache Flink at JET begins with the recognition that while Flink is powerful and that our primary job is to make that power approachable for everyone.

This realization led us to consider "What If? Abstracting complexities" as part of our diagnosis.

In this sesion, we will discuss how, ultimately, the core lesson we've learned is to hide the complexity, though not the capability, of the underlying system!

Talk 2: From Tables to Streams: Apache Flink for SQL Developers - Viktor Gamov (Confluent)

What if your SQL queries could process data as it happens instead of after it's stored? Apache Flink speaks SQL fluently, but it's not a database – think of it as a conductor orchestrating endless streams of data rather than a librarian managing stored records.

This session bridges the gap between traditional SQL and stream processing.

We'll explore:

• The Mental Model Shift – From "query the database" to "continuously process the stream" using intuitive analogies
• Flink SQL in Action: How familiar operations like SELECT, JOIN, and GROUP BY work on infinite data streams, plus temporal joins, time windows, and watermarks
• Table API: Programmatic control with declarative simplicity, bridging SQL and complete programming flexibility
• Flink AI: Real-time feature engineering and model inference on streaming data using SQL-like patterns
• Real-World Patterns: Fraud detection during transactions, live analytics dashboards, and event-driven architectures

You'll leave understanding not just how to use Flink SQL, but when and why it transforms traditional database skills into real-time data superpowers.

Perfect for: SQL developers and data engineers ready to make their queries travel through time.

Talk 3: Placeholder For Your Talk!

Our theme for this meetup is, clearly, Apache Flink. We have two great talks with excellent speakers and here we have a third slot, a bit shorter, for anyone who wants to fill it.

Do you have experiences with Apache Flink you'd like to share? Write to amsterdamjug@googlegroups.com and you'll get a short slot of 30 minutes, or less, depending on how many sign up!

Amsterdam JUG Meetup at Sociale Verzekeringsbank (SVB)

09 jun 2026 18:00 CEST

Sociale Verzekeringsbank, Van Heuven Goedhartlaan 1, Amstelveen, NL

Join in with the latest Amsterdam JUG Meetup at Sociale Verzekeringsbank (SVB), Van Heuven Goedhartlaan 1, 1181 KJ Amstelveen, Nederland.

Important notes:

• Bring your passport, or ID card, for identification, otherwise you will not be let in.
• When you register here on the Meetup page, please make sure to include your first and lastname. (If you have not done so, please drop a mail to amsterdamjug@googlegroups.com with your first and lastname.)
• There is free parking, if you send your license plate number to amsterdamjug@googlegroups.com.
• Vegetarian options will be available.

In this meetup, in addition to food, drinks, and networking, you will experience the following program and talks:

18:00 - 18:30: Doors Open and Food
18:30 - 19:00: Talk 1: Building Intelligent Java Apps: Agent Patterns, MCP, and the Future of AI Native Design - Daniel Oh (IBM)
19:00 - 20:00: Talk 2: The Mainframe, Java, and the Database - Jeroen Dijkmeijer (SVB) and Danny Calame (SVB)
20:00 - 20:30: Talk 3: Crafting the Ultimate Docker Image for Spring Applications - Pasha Finkelsteyn (BellSoft)
20:30 - 21:00: Talk 4: MCP Apps with Spring AI - Alexey Lihovodov (Indurex)
21:00: Exit

Abstracts

Building Intelligent Java Apps: Agent Patterns, MCP, and the Future of AI Native Design - Daniel Oh (IBM)

As AI rapidly evolves from model experimentation to production-grade applications, Java developers are increasingly faced with a new paradigm: designing intelligent systems that can reason, interact, and adapt.

This talk explores the emerging Java AI application development journey through the lens of agent-based architecture, with a focus on how the Model Context Protocol (MCP) and Agent2Agent (A2A) communication patterns are transforming the way we build intelligent, context-aware services.

We’ll walk through the foundational shifts in building AI-native Java applications—moving beyond single-shot prompt-response interactions to multi-agent coordination, persistent memory, and tool-augmented reasoning. We’ll also address the critical architectural trade-offs: performance versus flexibility, open source versus vendor-managed inference, local versus remote model deployment, and how to maintain security and observability in agent-based systems.

The Mainframe, Java, and the Database - Jeroen Dijkmeijer (SVB) and Danny Calame (SVB)

Details coming soon.

Crafting the Ultimate Docker Image for Spring Applications - Pasha Finkelsteyn (BellSoft)

Docker is the cornerstone of today's development! Let's overview quickly how we use it in JVM development and then transition to practical examples.

We will start with a simple Docker image containing a popular "one fat JAR" and look into its downsides (deployment speed, traffic volume). To address them, we will discuss the strategy of splitting the JAR into multiple layers and using multistage Dockerfiles, gradually improving our image.

Join me to learn how to build the ultimate Docker image for Spring applications.

MCP Apps with Spring AI - Alexey Lihovodov (Indurex)

MCP is already the de facto standard for connecting LLMs to tools and data, and earlier this year MCP Apps shipped as an official extension. Tools can now return interactive UI components that the host renders
directly in the conversation, and a single MCP server can light these up across multiple hosts without per-client
code.

This talk unpacks how MCP Apps fit into the wider MCP picture, and walks through building one with Spring AI. We'll also cover the rough edges, since first-class MCP Apps helpers aren't in the framework yet.

Bios

Daniel Oh is a Java Champion and Senior Principal Developer Advocate at IBM, where he leads efforts to advance cloud-native innovation through open-source technologies. Renowned for his ability to bridge technical and collaborative gaps, he empowers developers and organizations to build transformative solutions—from AI-driven applications and serverless architectures to resilient microservices. As a CNCF Ambassador and TAG DevEx co-chair, Daniel actively shapes the cloud-native ecosystem, fostering partnerships between enterprise developers, AI engineers, and platform engineering teams to accelerate hybrid cloud adoption.

Jeroen Dijkmeijer (SVB) and Danny Calame (SVB) are senior developers and DBAs at SVB.

Pasha Finkelsteyn has years of experience in software engineering and the team's leading roles combined with his passion for Java made Pasha know all the hidden details in this IT niche. As a Developer Advocate for Bellsoft, he educates the public on the latest software tools built by BellSoft and helps to create and test instruments for developers. He writes in Kotlin, speaks at conferences, composes new articles, and maintains his pet projects.

Alexey Lihovodov is an engineering leader and software engineer with deep experience in backend, platforms and cybersecurity at scale. Over his career, he's worked with a wide range of technologies and across every layer of the
stack, from low-level infrastructure up through data, frontend, and SRE. He's passionate about building great
engineering cultures, and, as for many these days, tinkering with AI has become his current focus.