Java Concurrency

**3D Workshop** * **Ontwerpen met Fusion360** * **Scannen in 3D** * **Het gebruik van 3D printers** **Je bent nu welkom in de nieuwe locatie NewTechPark** Je kunt ook online aan deze fysieke bijeenkomst deelnemen. De bijeenkomst is dan op de locatie te volgen. Als je [hier](w.j.put@hccnet.nl) vooraf een mailtje stuurt kun je dinsdagavond tussen 19.00 en 20.00 uur inloggen met Jitsi voor vragen, of ter kennismaking met hcc!3D. Online neem je deel aan de bijeenkomst met [https://wij.hcc.nl/3D](https://wij.hcc.nl/3D) [(Alleen toegang als je zichtbaar bent met voor- en achternaam. )](https://wij.hcc.nl/3d)

Hey everyone, We’re back with a new event in Amsterdam focused on building with AI in a secure and efficient way. ***Don't forget to RSVP now*** **TALK #1 - Breaching LLM-Powered Applications** **\- Overcoming Security and Privacy Challenges** This session explores the security and data privacy challenges of AI applications using LLMs, covering issues like prompt injection, key leakage, and data misuse. It highlights how general security flaws affect LLM behavior and provides strategies for compliance and best practices to build secure, LLM-powered applications. **Speaker : Brian Vermeer** Staff Developer Advocate for Snyk, Java Champion, and Software Engineer with over a decade of hands-on experience in creating and maintaining software. He is passionate about Java, (Pure) Functional Programming and Cybersecurity. Brian is a JUG leader for the Virtual JUG and the NLJUG. He also co-leads the DevSecCon community and is a community manager for Foojay. He is a regular international speaker on mostly Java-related conferences like JavaOne, Devnexus, Devoxx, Jfokus, JavaZone and many more. Besides all that, Brian is a military reserve for the Royal Netherlands Air Force and a Taekwondo Master / Teacher. **TALK #2 - Securing Multi-Tenant AI Platforms: Practical Lessons from OpenShift AI, GPUs, and MLOps** As more teams move from AI prototypes to shared enterprise platforms, security becomes a platform engineering problem: how do we let multiple teams train, experiment, and deploy models safely on the same infrastructure? In this talk, I’ll share practical lessons from building multi-tenant AI/ML environments on Kubernetes and OpenShift AI, with a focus on GPU-backed workloads. We’ll cover workload isolation, access control, GPU partitioning, namespace and quota design, supply-chain considerations, observability, and governance patterns for regulated environments. The session will stay engineering-oriented and vendor-neutral, with concrete examples of what can go wrong, what controls matter most, and how platform teams can enable AI adoption without compromising security. **Speaker : Luca Berton** Luca Berton is a cloud-native and AI platform architect based in Amsterdam. He works on enterprise Kubernetes, OpenShift AI, automation, MLOps, and secure infrastructure for large-scale and regulated environments. He is also the author of several technical books and courses on Kubernetes, Ansible, Linux, and AI/ML operations. **Agenda** * ​​​6:00 pm: Venue opens - ​Join us for Drinks and Pizza! * ​​​6:30 pm: Talk 1 * 7:15 pm: Talk 2 * ​​​20:30 pm: THE END

Thierry Berger is bringing an exclusive Rustlang themed [Techy Cards](https://github.com/ThierryBerger/techycards) edition, come to play and go home with your playable booster! Date: Tuesday May 19th 19H30–21H30 Location: Bunk Hotel Utrecht Catharijnekade 9, Utrecht, NL

**Please note:** registration for this event is **not** via meetup.com; this is an announcement only! See below on how to buy tickets for the event. **RustWeek 2026!** RustNL is incredibly excited to announce the 4th edition of our conference. The world's biggest Rust conference includes one day of workshops, two days of talks (in 3 parallel tracks), a hackathon, social activities, and more! The conference, on Tue & Wed May 19-20, is the main event. **Conference tickets for individual developers** The regular price for conference tickets for individuals are priced at €237.50. With this link, you can get a 10% discount on individual tickets: [https://event.onliveevent.nl/rustweek-2026/register?code=RUSTNL-MEETUP](https://event.onliveevent.nl/rustweek-2026/register?code=RUSTNL-MEETUP). More info: [https://2026.rustweek.org/](https://2026.rustweek.org/) If your employer pays your ticket, we ask you to buy an "Employer-paid" ticket (€413 ex VAT), to help cover the cost of the conference. **Come meet the Rust Project team members** We are proud to host the Rust All Hands for the 2nd time, which takes place later in the week. Folks from the Rust project teams will be at the conference, so it will be a great opportunity to meet them and attend talks in the "Project track", with each project team (language, compiler, library etc) presenting on a current topic. **Location** The conference is held at Kinepolis Jaarbeurs in Utrecht, right next to the central train station.

Are you a (Rust) meetup organizer or dreaming of becoming one? Join this session and get to know other meetup organizers! The meetup is on the first day of the conference at Kinepolis, during the first break, in the Reception room. The room is located across the entrance of the main stage on the 2nd floor. **Please note that you need a conference ticket to access the venue.** **What to expect / possible goals:** * Get advice on how to start your local Rust Meetup * Meet and network with other Rust meetup organizers from different cities and countries * Share experiences, successes, and challenges in running local Rust communities * Get insights on promoting diversity, inclusion, and accessibility in your meetup * Discover tools, resources, and collaboration possibilities between meetups

Do you want to meet fellow Women in Rust at RustWeek 2026? Join our friendly and vibrant community for lunch on Tuesday 19 May at 12.45pm CEST. Find us at a dedicated table in the lunch area! This will be an opportunity to share experiences, expand your network, and simply enjoy a chat with like-minded individuals. Please note that a RustWeek 2026 ticket is required to enter the venue. More info at https://2026.rustweek.org.

Every Tuesday, the group 024 Waalrunners go for a run at a distance of between 7km - 10km depending on the group. Everyone is welcome to join, you just need to turn up at 20:00 on Tuesday in front of Brouwerij De Hemel. There are different routes every time, and the group welcome all new people to join them. [https://www.facebook.com/024waalrunners-710731759317504](https://www.facebook.com/024waalrunners-710731759317504)

In the series of Trailblazers meetups this time we have a recurring guest from the Liberating Structures Meetup group, Robert van Lieshout! He will guide us through facilitating and working with Liberating Structures (LS). Liberating Structures are a collection of interaction patterns that allow you to engage groups of any size constructively towards the end result. They are based on 10 principles, such as “Practice Deep Respect for People and Local Solutions“ or “Engage in seriously-playful curiosity”. Liberating Structures are easy-to-learn, adaptable, and widely applicable. If you want to practice with LS, or want to experience them, this is the evening for you. But on top of that we will not just focus on the structures, we will also use them to help participants to gain insights in the theme of the evening: “*Changing the world, one conversation at a time*”. So, do not hesitate, invest in this evening to gain insight into what you can do to change the world. Program: * 17:00 Door opens * 17:30 diner * 18:00 Welcome and start of the session * 21:00 Closing drinks We will use a selection of LS that you can volunteer to facilitate, and one of them will be Social Network Webbing.

Donderdag 21 mei 2026 is het weer tijd voor onze Techday: hét vaste moment waarop we kennis delen, elkaar inspireren en nieuwe ideeën direct in de praktijk brengen. Deze editie pakken we het aan als een conferentie in het klein. Drie sprekers, drie verhalen, één middag – drie verhalen voor de prijs van één. Wat kun je verwachten? **Dirk neemt een kijkje onder de motorkap van AI** AI voelt voor veel mensen als magie. In deze talk probeer ik de magie weg te nemen door een kijkje te nemen onder de motorkap. Een essentieel bouwblok van moderne AI is een neuraal netwerk. Als je begrijpt hoe een neuraal netwerk werkt, is het een stuk makkelijker om te begrijpen hoe en waarom een LLM werkt. De beste manier om iets te begrijpen is door het te bouwen, vanaf scratch. Dus dat gaan we in deze talk doen. Door dat te doen leren we over artificial neurons, activation functions, backpropagation en meer. **George vertelt hoe AI Cyberaanvallen verandert** George Schizas (extern), voormalig IT Manager, nu werkzaam als CISO, vertelt over zijn ervaringen in de Cloud Cyber Security en hoe hackers met behulp van AI nieuwe aanvalsmethoden kunnen gebruiken om kwetsbaarheden op te sporen en te exploiteren. Hij geeft voorbeelden van manieren om in Kubernetes omgevingen in te breken en noemt manieren om dit tegen te gaan. **Roland duikt in de wereld van de fraude fabriek** Als ontwikkelaar kom je dagelijks in contact met technologie en de laatste jaren natuurlijk ook vaak met AI. JIJ snapt heel goed wat de voordelen en de gevaren zijn, maar hoe leg je complexe onderwerpen als AI gegenereerde afbeeldingen, Voice Phishing en Hallucinaties uit aan je ouders, de buurvrouw, of je kinderen? Ik neem jullie mee in een realistische situatie waarin Anna en haar familie opgelicht wordt met behulp van verschillende technieken en hoe dit oplichters-landschap met behulp van AI verandert. **Wanneer:** Donderdag 21 mei 2026 **Wat:** Techday – conferentie-editie “AI kansen en valkuilen” **Voor wie:** Iedereen (!) die nieuwsgierig is en wil leren **Agenda** 14:45 - 15:00 - Inloop 15:00 - 16:00 - Neurale netwerken 16:15 - 17:15 - AI risico’s en kansen 17:15 - 18:00 - Eten 18:00 - 18:45 - Fraude fabriek We zien je graag op de Techday!

(english/german below) **Bitcoin Pizza Dag!** Op 22 mei 2010 betaalde programmeur Laszlo Hanyecz 10.000 BTC voor twee pizza's — de eerste gedocumenteerde aankoop met bitcoin. Hij plaatste een bericht op een forum waarin hij BTC aanbood voor pizza; een andere gebruiker ging akkoord, bestelde de pizza's en leverde ze af. Die transactie werd later bekend als "Bitcoin Pizza Day". Laszlo bewees dat Bitcoin als ruilmiddel gebruikt kan worden. **Sluit je bij ons aan voor pizza-avond bij De Pizzabakkers! (vanaf 18:00)** RSVP zo snel mogelijk; we moeten reserveren bij De Pizzabakkers en er is beperkte plek. Zorg dat je je geladen Lightning-wallet meeneemt! *** **English: Bitcoin Pizza Day!** On May 22, 2010, programmer Laszlo Hanyecz paid 10,000 BTC for two pizzas — the first documented purchase using bitcoin. He posted on a forum offering BTC for pizza; another user accepted, ordering pizzas and delivering them. That trade later became famous as "Bitcoin Pizza Day," Laszlo proved that Bitcoin can be used as a medium of exchange. **Join us for pizza diner at De Pizzabakkers! (from 18:00)** Please RSVP as quick as possible as we need to make a reservation at De Pizzabakkers and there is only limited space. Be sure to bring your loaded lighting wallet along with you! *** **Deutsch: Bitcoin Pizza Tag!** Am 22. Mai 2010 zahlte Programmierer Laszlo Hanyecz 10.000 BTC für zwei Pizzen — der erste dokumentierte Kauf mit Bitcoin. Er postete in einem Forum und bot BTC für Pizza an; ein anderer Nutzer akzeptierte, bestellte die Pizzen und lieferte sie aus. Dieser Tausch wurde später als "Bitcoin Pizza Day" bekannt. Laszlo bewies, dass Bitcoin als Tauschmittel verwendet werden kann. **Begleite uns zum Pizza-Abend bei De Pizzabakkers! (ab 18:00)** Bitte antworte so schnell wie möglich; wir müssen bei De Pizzabakkers reservieren und es gibt nur begrenzten Platz. Nimm unbedingt deine geladene Lightning-Wallet mit!

**RSVP here via EventBrite [here](https://www.eventbrite.nl/e/you-and-your-brand-a-casual-networking-hour-tickets-1984283125243).** Expand your visibility. Join a casual online time to share about you, your brand and business, and learn more about other business owners, locally and globally. Share upcoming events and workshops, too. After each business owner gets the spotlight to share, we then move into a topic-oriented discussion. This month, the topic is begin chosen by [Isabella Maria Noguera, MSc](https://www.linkedin.com/in/isabellamarianoguera/) over of Be Your Brand Consulting. Every session closes with gratitude and a creative activity, so have a pen and paper, tablet, or something available in case we write/create/draw. **RSVP here via EventBrite [here](https://www.eventbrite.nl/e/you-and-your-brand-a-casual-networking-hour-tickets-1984283125243).** *-* *\*\*\*The only requirements are a minimum age of 18 years old, be a business owner or preparing to launch,* *and **at least three attendees** register to make it a worthwhile hour for everyone.\*\*\**

Come along, lovely queer hikers! 🌿✨ This time we’re serving an easy-going queer nature moment with a short loop through **Landgoed Heidestein** near Zeist. Think dreamy forest paths, shimmering fens, a peaceful forest pond, and heather fields - a lot of diversity for such a short walk :) We’re teaming up with **Cocktail (COC’s group for LGBTQIA+ refugees & asylum seekers)** for this event, so besides soaking up nature, we’re creating space for connection, sharing stories, and learning from each other’s journeys and experiences. Expect a vibe that’s part hike, part picknick, part wholesome community exchange. 🌈 Bring your snacks and blankets, as we’ll pause along the way for a relaxed picnic moment together. Because queer joy isn’t just about where we go, but who we walk with. 💖 **Practical info** 📏 **Distance:** 5 or 7 km (loop walk) 📍 **Start:** Bus stop Prinses Margrietlaan, Zeist (5km option) Driebergen-Zeist station (7km option) 🏁 **End:** Back at the starting point 🥾 **Level:** easy - chill pace 🤝 **Meeting point:** outside the train station **Driebergen-Zeist at 13:45** or bus stop **Prinses Margrietlaan (Zeist) at 14:20** ❗You’re welcome to join from another direction. If you come by car you can park at P+R Driebergen-Zeist. Please note: we published this hike with Cocktail simultaneously, which is also why we lowered the participant number from Hiking Queer NL's side. Pack your: 🍱 snacks 🚰 water 🧥 rain coat/umbrella ☀️ sun screen 🏳️‍🌈 anything else you might need ❌ If you signed up and cannot make it in the end, please cancel your RSVP attendance so we know how many people will show up and someone else can take your place instead. 💗 A voluntary donation helps us to keep the Meetup group up and running :) you can either pay via a Tikkie or in cash after we finish the hike. *Hiking Queers Netherlands & Cocktail (COC)*

\# This meetup is around a third\-party organizer\, Focus Filmtheater\. You can either purchase your ticket online or right before the session\. **Seats are numbered**. # **Title**: The President’s Cake **Language**: Arabic **Subtitles**: English **Length**: 106 min **Director**: Hasan Hadi **More info**: https://www.focusarnhem.nl/agenda/english-subs-the-presidents-cake/ **Ticket link**: https://www.focusarnhem.nl/tickets/144299/ **Synopsis:** In poverty-stricken 1990s Iraq, young Lamia is selected to prepare a cake for the President’s birthday. Because basic ingredients are hard to find, Lamia goes on a journey in search of eggs, flour and sugar. It becomes a tender, tragicomic odyssey, offering a child-eye’s view of life under authoritarianism. Hasan Hadi’s affecting debut feature follows 9-year-old Lamia. She is tasked with bringing a cake to school for the President’s mandatory birthday celebration. Against a backdrop of crippling poverty and food shortages, she journeys from her marshland home to a nearby city in search of ingredients. Coming along with her are her grandmother Bibi, her best friend Saeed and her beloved pet rooster Hindi. Shot on location in Iraq with nonprofessional actors, this tender, tragicomic odyssey offers a poignant child’s-eye view of life under authoritarian rule. The film was inspired by Hasan Hadi’s childhood memories of 1990s Iraq under Saddam Hussein, and was awarded the Caméra d’Or at Cannes for best first feature. **How it works**: I will be at Focus around 18:30, where we can meet before the movie starts. You can message me to find us. Screening starts at 19:00. After the movie, we can have a drink together. Hope to see you soon!

**Important time note:** Please plan on arriving between 5:30 and 6:00 as the elevators lock after 6 and you'll need to message us and we'll need to come get you. The building address is 4450 Bridge Park The entrance is 6620 Mooney St, Suite 400 You will need to scan your ID at the door to get a visitor badge. **Abstract** TBD **YouTube Link** TBD

WQC has weekly Thursday night social nights at the Westerville Java Central. Come and grab a coffee and connect with the community: low stakes, chill environment, and tasty drinks. No registration is required; come as you are.

Customer identity resolution becomes increasingly complex as organizations scale across multiple systems, regions, and data formats. Traditional rule-based approaches often fail to keep up with data variability, require constant manual tuning, and struggle with real-time processing needs. This session presents a practical approach to building a scalable identity resolution pipeline using AWS services and modern AI techniques. The architecture combines data ingestion through Amazon S3 and AWS Glue, transformation pipelines using Spark on EMR, and machine learning models deployed via SageMaker for entity matching and standardization. Graph-based relationship modeling is implemented using Amazon Neptune to improve resolution accuracy by incorporating household and shared attribute context. We will walk through how machine learning models can be used for name and address normalization, how intelligent blocking strategies improve matching efficiency, and how feedback loops can be introduced to continuously improve accuracy. The session also highlights how serverless components such as AWS Lambda can be used for orchestration and real-time processing. **SPEAKER BIO** Mosaic Syed is a Senior Data Engineering and Cloud Solutions Architect with over 20 years of experience designing and delivering scalable, secure, and high-performance data solutions across global enterprise environments. https://www.linkedin.com/in/mosaic-basha-syed-92300856 **CALL FOR SPEAKERS** Learn more: [https://www.awscolumbus.com/get-involved/](https://www.awscolumbus.com/get-involved/) **THANK YOU** *VEEAM* for hosting our meetup! To learn more about *Veeam*, please visit their website: [https://www.veeam.com/](https://www.veeam.com/) **DIRECTIONS** 8800 Lyra Dr #450 · Columbus, OH go to 4th floor. **Want to sponsor the pizza and/or bar tab?** Please contact me if you would like to sponsor this meetup's pizza and/or bar tab: angelo@mandato.com

Join the CONNECTED Westerville Mastermind Group for a dynamic afternoon of B2B networking! This event is perfect for professionals looking to expand their business connections, share insights, and foster collaboration within the community. Whether you are a seasoned entrepreneur or just starting out, this event offers a valuable opportunity to exchange ideas, build relationships, and grow your network in a supportive environment. Connect with like-minded individuals, explore potential partnerships, and discover new opportunities for professional growth. Don't miss out on this chance to enhance your business network and take your career to the next level with CONNECTED Westerville Mastermind Group! We meet the 4th Monday of every month from 11am-1pm. Welcome and general networking from 11am - 11:30am with core meeting 11;30 - 12:30 and a final round of networking from 12:30 - 1pm.

We will show how to build custom agents with Microsoft Agent Framework. Attendees will learn how to build and custom host agents when Microsoft Foundry is not a viable option.

**How to take control of your subconscious and harness its power!** Join us for an eye-opening lecture where the speaker will break down complex ideas in a clear and practical way. You’ll gain insights into: ✅ The true definition of the subconscious ✅ How it generates unwanted emotions ✅ Its real purpose and function ✅ What determines the pressure it exerts on you And the most important topic: **How do you take control of your subconscious!** But this isn’t just another lecture where you sit and listen passively. It’s interactive and engaging—you can ask questions at any time. 📅 Reserve your spot now! Seats are limited, so don’t wait too long to sign up. Location: 1266 Dublin Rd, Columbus, OH 43215 Hosted by the Hubbard Dianetics Foundation

**Latest Dojo Location!** **Knotty Pine Brewing** 1765 W 3rd Ave, Columbus, OH 43212 We're going to try a new dojo location for a few weeks and see how it works Dojos are informal Python group study sessions where everyone interested in Python gathers to learn about Python, help others with Python, or just hang out. Everyone is welcome from Python beginners to experts. Bringing a laptop is encouraged (we'll have extension cords and power strips). If there's something you want to learn leave a comment on this invite so we can plan ahead. We're looking for speakers for our Monthly Meetups! Fill out the form if you are interested in presenting to the Python Community. https://forms.gle/ehSfUAC2WgR34Crq9