Original LinkedIn post

A week at JCrete® is hard to explain if you've never been to an unconference.

No speaker lineup. No fixed agenda. No tickets to buy. Everyone is speaker and audience at once. And it's one of the most valuable weeks of my year.

Back home – the last conversation happened at a Berlin baggage carousel – here's what stayed with me.

Every morning we built the day ourselves at the “Marketplace”: anyone proposes a topic, we vote, and the schedule appears. And if a discussion runs out of time, you simply propose a follow-up session. That's what happened with Rémy Forax's Project Valhalla session: in part one we got through only 17 of 49 slides – not from lack of time, but because there were so many questions – so we ran a second part later. If a session isn't for you, the “Rule of Two Feet” applies: stand up, walk out, find a better spot. No one takes offense.

The topics ranged widely. Analog computers solving differential equations in near real-time (Thaddeus Müller-Sarnowski). Building personal assistants with AI (Oleg Šelajev) and “proper vibe coding” (Viktor Gamov and Pasha Finkelshteyn). And a room full of people debating what we should teach the next generation of developers (Kaitlyn Hornbuckle, Connor Whiting, and Jakub Jakubowicz).

I ran two sessions myself: one on how to get colleagues and decision-makers to care about modern Java, and one on JVM internals – “From Compressed Oops to Compact Headers”. Rather than walking through slides, I asked what people wanted to know and dug in. Special thanks to Kirk Pepperdine for the deepest questions I've ever had on this topic.

But JCrete is never only about Java.

We hiked through a gorge and were waved over to a barbecue by around 50 locals at a small church – course after course of meat, fish, wine, and melon. I went diving for the first time, ten meters down (thank you, Arno Koehler), and joined a wine tasting (thank you, Yorgos SASLIS). One evening the Cretan wind made grilling impossible, so a bakery grilled for all 150 of us (thank you, Alexius Dionysius Diakogiannis). And long evenings together, including at Heinz and Eleni Kabutz's home.

One of the highlights was JCrete4Kids. We introduced local schoolchildren to programming with VS Code and a machine-learning-enabled Scratch. What got to me: the kids didn't stop when the workshop ended – they simply kept building. Huge thanks to John Kostaras, Kaitlyn Hornbuckle, and Cassandra Chin for making it happen.

Thank you, Heinz Kabutz, and the whole Disorganizers team for another special week. Besides those named above: Andres Almiray, Marc Hoffmann, Melissa McKay, Ixchel Ruiz, and Dmytro Vyazelenko.

The conversations don't end when the event does – they carry into the year. Two more unconferences are already set: – JChateau, 10–14 March 2027, Loire Valley, France – JAlba, 20–23 May 2027, Edinburgh

Less sun, no beach – but the same deep conversations about Java. ;-)

What's the most valuable thing you've ever taken home from a conference?