Tom Cools

Suddenly there is a 1000 of you following me! Welcome 😁 I'm Tom, geeky guy from Belgium, very passionate about programming with a heavy focus on #java technologies. I post about software development, public speaking and career. Glad to have you here! <3

Day 2 @devoxx.com! And we got a caricature artist 🤣. Come on by the #timefold booth.

Finally! I get to talk about what we've been cooking up at Timefold when it comes to dragging planning optimization (sometimes kicking and screaming) into the #agentic age. 🔥 You can sign up for the webinar here: timefold.ai/events/optim... See you there?!

If you are in Antwerp for @devoxx.com this week and get overwhelmed by the amount of different beers we have, no worries! You can optimize your evening using our #timefold Beer Plan app. 😅 timefold.beer And yes, apparently there is a top level domain for .beer 😂

I posted about Jev a couple of days ago, and it got me thinking where this new AI model fits in. In this world of overloaded AI terminology, calling it a "model" has had the side-effect that people immediately compare it to GenAI models. But that should be clarified. timefold.ai/blog/system-...

One of my new favorite things is to ask Claude to add architecture validation tests using @archunit.bsky.social whenever we want to "codify" decisions. Actual executable deterministic validation = 😍 Works like a charm. Move beyond markdown and prayers, add some actual validation in there! #java

NEW POST Jim Highsmith explains that effective writing from a practitioner is a style distinct from academic writing or thought-leadership content. martinfowler.com/articles/pra...

Looking for input/feedback from Java developers on 2 different topics: 1. Is there interest in a JavaFX workshop/conference/training in Belgium? 2. Is there interest in a gathering with fellow Java developers working on scientific topics (writing java code, not only using 3th party code) #java

Anybody interested in submitting an "Agentic Loops / Workflows" Deep Dive or Conference session? 🔂 dvbe26.cfp.dev

The new edition of Java Annotated Monthly is live! 😎 This month, we are featuring content from @tomcools.be, plus a fresh roundup of the best reads across Java, Kotlin, AI, and other tech news👇 jb.gg/sf2lou

Never thought I'd be one of those people holding my macbook open while boarding an airplane but here we are. Bye Lisbon, till next time! I make my escape to Belgian weather! 😅

Alright @bejug.bsky.social #java user group friends. We normally take a break during the summer, but I think we can have a nice BBQ, drinks and Java documentary watching somewhere... who's in?! (other #jugs feel free to steal the idea 😊) www.youtube.com/watch?v=8jrK...

Ok, so @pi.dev is pretty cool. It's great to be able to write deterministic code to steer my agents. Feels much smoother than the bash-y hooks and such from others. Also custom tool calls, easy peasy. I guess I know what my next conference talk is going to be about. 😅

On my way to work, driving behind a truck with the following text on tailgate/doors. "We can see you are behind us... thank you for your support!" 😅 You're...welcome?

When looking for tech events, hacks, & meetups, where do you go to find them? As the organiser of @virtualjug.bsky.social & launching a new dev event, I want to make sure we show up in the spaces you actually use. Let me know in the comments 👇

The last Belgian #Java User Group before the summer stop is in the books! Thank you again to @oniryx.be for hosting us every year in June since we started! A big massive thank you to @glycin.bsky.social and @ted.dev for presenting #spring and #eventsourcing See you all after summer! ☀️

First thing my kid says to me when he woke up: "Daddy, that's Duke on your tshirt" Proud dad moment. 😅 #java We have a @bejug.bsky.social event today, so was already wearing this.

Life is a matter of perspective. Sometimes all you need to do is take a few steps to the side and what looked like "stop believing" turns out to say "never stop believing." ✨ Thank you Wintercircus Ghent (our Timefold homebase) for such a clear example that where you stand changes what you see. 🎪 😅

BeJUG is back and we're coming to Ghent! 🇧🇪☕ Join us for two great talks: 🗄️ Event Sourcing with @hanneslowette.net 🎙️ The story behind JCast with Maarten Casteels Hosted by www.inetum.com/be/nl.html. Many thanks for hosting us again! 👉 RSVP (free): www.meetup.com/belgian-java... #Java #BeJUG

International adapters! Thanks for the reminder @devoxx.uk 😂

Hi folks! If you are @devoxx.uk this week, i'd love to meet you there! Come to my session on "dealing with change" on wednesday, or just tap me on the shoulder for a nice conversation... i am bringing belgian! 🍫

Job hunting as a developer is a nightmare, right? Tell me your stories of navigating the recruitment process as a dev looking for a job, and if you've been in the game for a while, tell me how it's changed lately (I want to use these stories on the Modern Software Engineering channel)

Last Wednesday, we released the newest version of Timefold Solver, 2.0. It's a major version, which can look a bit scary. Upgraded 15 projects... time: under 10 minutes. 😊 Read about that experience here: timefold.ai/blog/timefol... Big thanks to Moderne for their work on #OpenRewrite. 😊

I know first hand that it's scary to stand up and speak at a conference for the first time. That's exactly why we given them support to take to the stage at @devoxx.uk. If you're attending do come along and support these aspiring speakers!

Looking for work. Will DevRel for coffee or wine 😁

A project I've wanted to build for a while, mainly to remind myself to submit talks to CFPs. - Get the data from javaconferences.org - Create a video with the data using Remotion Could be less obnoxious, but that's for the next iteration. 😇 #java #conferences

Just a few more weeks until @devoxx.uk , where I will be presenting probably the most personal and important talk I have ever created, for the first time in the UK. Because yes, even Java Champions struggle with change. Give it a <3 on the companion app to not miss it: m.devoxx.com/events/devox...

When doing an employee schedule roster for 30 people, you end up with more possible combinations than atoms in the universe. Excellent talk by @tomcools.be at #VDC26!

🚀 2026 starts strong for @bejug.bsky.social! We’re back in Kortrijk with an amazing guest @agoncal.bsky.social Big thanks to Sweet Mustard for welcoming us in their brand-new offices 🍕 Food is on us 👉 Join the fun www.meetup.com/belgian-java...

Thanks @tomcools.be for reminding me about my comics 😃 Here's one about modern engineer's problems. #devhumor #softwareengineering #ai

How fast is Java 25? timefold.ai/blog/how-fas... by @tomcools.be

Hey Belgian Java devs, Amsterdam is calling! ☎️ Voxxed Days Amsterdam, April 1–2, 2026 Now with BeJUG as an ambassador, making it your Java community event too! 2 days of code, talks & networking. Don’t miss it → amsterdam.voxxeddays.com#ticket Give BeJUG a follow: @bejug.bsky.social #community

One of the coolest things about our @bejug.bsky.social community? Everyone can participate and help out. Check out this amazing banner @lomagnette.bsky.social made!

A @kevlin.bsky.social during my informal #speakertour after the @devoxx.com conference! Seen on the Meir shopping street. Spotted by @lomagnette.bsky.social, picture by @hanneslowette.net. 😊

First talk of my #devoxx, @mydeveloperplanet.com talking about...what else... AI agents.

#Devoxx talk trial run in front of a "live" audience. 😅 If you are at the conference, do say hello when you see me. 😊

# Meetup telling me interesting group in Belgium no longer has an organizer. Me:

Not me FOMO submitting to #jfall on the very last day 🤣. If you haven't yet, you got a couple more hours to do so! It's a great conference!

Tom Cools - DevRel @Timefold | Conference (Keynote) Speaker 🗣️ | #Java Champion | @BeJUG Organizer @tomcools.be

45 more minutes folks! 😅

Amazing news 💥!!! JavaOne returns in March 2026 ❣️ Checkout all its details and save the date 🎉!!!

Books and Wine, lose track of time. 😊 #luddites #antwerp.

Time for our yearly stop at Oniryx 🤩. We got great food and drinks. Weather is epic and we got 2 cool talks lined up! 🤩 Let's Go!

Companies use the word "revolution" a lot to hype up their services. "Revolution" also means (in physics): One revolution: one full turn/360 degrees . So when you see the word, ask yourself: "is this really something new, or is this just a short spin before going the same direction as before".

☀️ Great talks, tasty food, cold drinks, and an outdoor venue—what more could you want? Join us on Thursday, June 19 for the next @bejug.bsky.social event! We’re taking Java to the park for an evening of tech & chill. 🌳🍻 Spots are still available, grab yours now 👉 www.meetup.com/belgian-java...

Did you miss @tomcools.be‬ Devoxx UK talk "LLMs can't optimise schedules, but AI can!" Watch it now and discover Timefold, a Java-based AI solver that excels at complex scheduling. Session link - buff.ly/Oj040Ck

Still plenty of space for the last meetup before our Summer break! 😊 Alex is a top rated speaker at conferences like Devoxx, so we are honored to have him with us! 🤩

FYI, if you need to compare 2 objects in a #java test, do not manually compare all fields by calling the getters. Instead, do it with 1 line of AssertJ: medium.com/@lucascalebe...