September 2026: From Wedding Optimization to Framework Freedom

Join us on Tuesday, September 15th for another JUG Noord meetup in Groningen, featuring constraint optimization for real-world planning problems and practical approaches to keeping Java applications independent from the frameworks they use.

📅 Date & Time:
Venue opens: 16:30
First talk starts: 17:00
Food & drinks: Provided between the sessions

📍 Location: Kempkensberg 12, Groningen

🚨 Important: Signing up and valid identification are mandatory for entry. If the name on your Meetup profile does not match your ID, please contact Martijn (organizer) with your full name.

🇬🇧 "You May Now Optimize the Wedding": Optimizing the Seating, Bachelor Party, and Honeymoon with Constraint AI by Tom Cools (Timefold)
Every developer has been there: sitting at a life event, thinking "could I automate this?" The answer is yes. And this talk will show you how.

There is a whole class of problems that AI alone cannot solve: scheduling, routing, and planning challenges where every decision affects every other decision. Timefold tackles these in production every day, across logistics, manufacturing, healthcare, and yes, apparently also weddings.

We will use the most important weekend of your life as our excuse to explore constraint optimization in practice, from seating charts to pub crawls to honeymoon itineraries, with real code, real constraints, and real solver magic.

You will leave knowing how to turn any "could I automate this?" moment into a working optimization solution.

🇬🇧 Java Beyond Frameworks: Avoiding Lock-In with Agnostic Design by Rijo Sam (ABN AMRO Bank)
The Problem: Modern Java apps often get stuck in their frameworks. Tools like Spring Boot and Quarkus speed things up, but they come with hidden costs such as vendor lock-in, heavy dependencies, and rigid architecture. So what happens when your app outgrows the framework or something better comes along?

The Solution: This talk introduces a layered approach to Java development, isolating framework dependencies while keeping core logic pure with Java and Jakarta EE. Through examples, you’ll see:
- Strategies for replacing framework-specific annotations
- Techniques to decouple business logic from frameworks
- Approaches to cloud integration without framework coupling

Trade-Offs: Yes, this demands more upfront effort, including writing custom persistence layers, rigorous tests, and meticulous documentation. But the payoff is code that’s adaptable, testable, and maintainable across frameworks, teams, and decades.

Key Takeaways:
- Practical patterns for agnostic design
- When (and when not) to adopt this approach

About the speakers
Tom Cools is a Developer Relations Engineer for Timefold, Java Champion and leader of the Belgian Java User Group. Tom has a decade worth of experience delivering systems and loves to share not only knowledge but also passion for our craft. You can read more at his blog (http://www.tomcools.be) or follow him on Bluesky (@tomcools.be).

Rijo Sam is a software developer and public speaker based in the Netherlands. He possesses extensive experience building applications in the payments and credit sector of the banking domain.
Outside of work, he’s usually on his bike trying to beat his cycling buddies.