Microservices

**Um was geht es dieses mal?** Dieses Mal haben wir zwei Talks für euch! **Performance und Portability in Data Analytics mit DuckDB & Co. - Niklas Niggemann** Moderne Data Teams kämpfen mit zwei Kernproblemen: Performance und Portability. Dieser Vortrag zeigt anhand umfassender Benchmarks von DuckDB, Polars und Pandas mit Datensätzen von wenigen Gigabyte bis zu mehreren Terabyte, wie Ausführungsmodelle, Dateiorganisation und Speicherverwaltung die Performance beeinflussen. DuckDB liefert konstant niedrigen Speicherverbrauch, Polars erreicht durch Parallelisierung hohe Geschwindigkeiten – doch sobald mehrere Engines „schnell genug" sind, zählt Flexibilität. Abschließend zeigen wir deswegen, wie Frameworks wie Ibis die analytische Logik von Engines entkoppeln und so lokale Entwicklung, Cloud-Deployment und Plattform-Migrationen ohne teure Neuentwicklungen ermöglichen. **Design Patterns - Wie sie dir helfen, ausdrucksstärkeren Code zu schreiben - Christian Ambach** Vor über 30 Jahren veröffentlichte die Gang-of-Four ihren Klassiker "Design Patterns. Elements of Reusable Object-Oriented Software". Viele der Muster erfreuen sich heute großer Beliebtheit und es sind eine Menge von Patterns dazugekommen, nicht nur auf Design-, sondern auch auf Architektur- und Organisationsebene. Wusstest Du, dass Du wahrscheinlich schon Design Patterns einsetzt, ohne es zu merken?In diesem Vortrag wird betrachtet, wie bekannte Frameworks und Bibliotheken – zum Beispiel das Spring Framework – auf Design Patterns setzen und wie die Teilnehmer diese Muster vielleicht schon ganz selbstverständlich in ihrem Code verwenden. Gemeinsam werfen wir einen Blick auf eine Auswahl von Design- und Architekturpatterns, entdecken Good und Bad-Practices und wie man Patterns gezielt einsetzen kann, um Code noch ausdrucksstärker zu machen. **Hybrides Setup!** Wir freuen uns, euch bei uns in den Räumen der codecentric AG in Dortmund willkommen zu heißen. Vor Ort versorgen wir euch mit Snacks und Getränken und freuen uns gleichzeitig über interessante Diskussionen und einen guten Austausch. Für alle, die es nicht zu uns ins Office schaffen, werden wir das Meetup Hybrid durchführen. Der Stream beginnt ca. 10 Minuten später, damit wir vor Ort ausreichend Möglichkeit für persönliches Kennenlernen haben. Den Live-Stream findet ihr auf dem [YouTube-Channel ](https://www.youtube.com/@codecentricAG)der codecentric AG. **Wichtig - Absage bitte rechtzeitig:** Wir bestellen das Essen bereits 3 Tage vor dem Meetup. Falls ihr doch verhindert sein solltet, bitten wir euch um eine rechtzeitige Absage. Das ist wichtig, damit wir nicht unnötig Essen verschwenden müssen. Vielen Dank für euer Verständnis! **Anreise:** Per Zug: Vom Dortmunder HBF sind es ca. 10 Minuten zu Fuß. Mit dem Auto: Rund um das Office gibt es einige Parkflächen, dazu befinden sich in dem Parkhaus der Thier-Galerie weitere Parkplätze.

**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)

We delen onze doelen en maken plannen voor de komende week. Iedereen is welkom. We kijken er naar uit om jouw verhaal te horen.

Hi Everyone, This is our weekly open hackerspace evening! Usually from 19:00 :-) Feel free to drop by, come and nerd with us! See this Tuesday! We're in room 126, ring the room number and we'll open the door. We're located on the first floor

Every Tuesday, the group 024 Waalrunners goes for a run at a distance of between 5km - 10km. Everyone is welcome to join, you just need to turn up at 20:00 on Tuesday in front of Cafe De Hemel. There are different routes every time, and the group welcomes all new people to join them. After the run we usually stay for a drink at De Hemel. https://waalrunners.activedates.nl https://chat.whatsapp.com/CRXG7x9HQUw4Q1qCrNzXn4?mode=ems_copy_t https://www.facebook.com/024waalrunners-710731759317504

Join us for an evening of good vibes! Whether you’re a local or an expat, Mingle Mania is the perfect place to socialize and make friends or even to practice languages. 🤝🤼‍♂️💬🙋‍♂️🫂 👉 Join [https://chat.whatsapp.com/GopSuzuFKRBKeYVKQrX4pE](https://chat.whatsapp.com/GopSuzuFKRBKeYVKQrX4pE) The group has many regular members, we intend to do various type of events, the goal is to build a strong community for all sorts of activities. If you have an event idea that you would like to see happen, let us know. We generally have about 20 participants, the age is between 20 and 60 averaging somewhere around 30, language exchange is not strictly enforced, culture exchange happens naturally. **mingle** (verb, intransitive): to move among people and talk to them, especially at a social event. 📍 **What We Are:** * A diverse group of locals and expats * ...going out at least every Tuesday 😊 🆓 **Event Details:** * It is free to join and operated on a voluntary basis! * Please honor the bar by ordering at least one drink.

The first of hopefully many peer Satsang gatherings! This is an open, equal and low-key gathering for spiritual seekers from all walks of life to get together, talk, feel connected and grow. The gathering will last for about two hours. Bring questions, thoughts, or just your presence. We'll see what unfolds once we're there. If you're interested but can't make the currently indicated time, the event is full or you have any other questions, get in touch with me at thijshugenholtz@gmail.com and we'll see what we can do! Location: Buurtcentrum Hart van Noord, Trumanlaan 60 Utrecht but the entrance is opposite Geallieerdenlaan 24

**ArnhemJUG** We are excited to announce that we are welcomed by Avisi for the March meetup. **Agenda** * 17:00 CET walk-in * 17:30 – 18:30 Food and drinks * 18:30 – 19:30 talk: **Koog your own AI! Delicious recipes** by **Simon Vergauwen** * 19:30 – 19:45 break * 19:45 – 20:45 talk: **Domain-Driven Design** by **Dirk Groot** * 20:45 – 21:30 drinks **Koog your own AI! Delicious recipes** Koog is an open-source Kotlin framework for building robust, and production-ready AI agents. Developed, and battle-tested in their own products by JetBrains! In this session we’ll build an agent, and explore various techniques to tackle different kinds of problems, and complexity. How we can use model-context protocol (MCP) to give our agent access to external tools, and how to build custom tools to integrate with your own systems. How to define flexible graph workflows to design complex agent behaviors. If you're not cooking your own AI Agents yet, you should! Join me and I’ll give you a taste of Koog. **About** **Simon Vergauwen** **Developer Advocate at JetBrains & OSS (arrow-kt) Maintainer** **Software engineer from Antwerp, Belgium.** Interested in everything functional, and Kotlin. Loves OSS, cooking, snowboarding and Fallou **Domain-Driven Design** What name should I give this entity? How should I deal with ambiguous terminology? Where should business rules be implemented? Is this validation part of the domain logic, or does it belong to the application layer? Which entities should be within the scope of this database transaction? In this talk we explore how the **Domain-Driven Design (DDD)** methodology helps answer questions like these. We will cover the key DDD concepts, including **Ubiquitous Language**, **Bounded Context**, **Aggregates**, **Entities**, and **Value Objects**, and discuss how they fit within a software architecture. The session is built around a practical example, so you will not only learn the theory behind DDD, but also see how these concepts can be applied in real-world software development. **About Dirk Groot** I'm a software engineer with more than 25 years of experience. Since my early teens, sofware engineering has been my greatest passion.

Hi✋ At[ Data Tribes ](https://www.datatribes.nl/)we organise Meetups because we truly care about sharing knowledge both inside and outside the organisation. We believe that it is beneficial to us and to the market as a whole to connect, create, learn and grow together! **The agenda** // Doors open 6.00pm // Drinks and Pizza’s 6.30pm // Start presentations 7.00pm // **Meni Shmueli - Distributed Computing Unpacked** // Start networking 9.00pm // End Meetup 9.30pm Greetings, Data Tribes Inc.

**DDSCC Meetup 7** 📅 **Datum:** Vrijdag 27 Maart 2026 🕐 **Tijd:** 12:30 – 17:00 📍 **Locatie:** Rubicon Cloud Advisor, Leusderend 36, 3832 RC, Leusden **Wat kun je verwachten?** **Agenda** * 12:30 – Inloop met koffie en lunch * 13:30 – Opening door DDSCC * 13:45 – Introductie door Rubicon Cloud Advisor * 14:00 – Jasper Oosterveld: With Great Power Comes Great Labeling: Sensitivity Labels in de Praktijk * 14:45 – Pauze * 15:15 – *Jeroen Bijdevier:* Je omgeving op orde voor veilig en optimaal Copilot gebruik * 16:00 – Ronde tafel gesprekken * 16:30 – Borrel & netwerken (tot 17:00 uur) **Session description:** **Jasper Oosterveld - With Great Power Comes Great Labeling: Sensitivity Labels in de Praktijk** Veel organisaties hebben inmiddels sensitivity labels geïmplementeerd als basis voor data security in Microsoft 365. Maar zodra je voorbij de basis komt, ontstaan er nieuwe vragen. Hoe ontwerp je een werkbaar labelmodel? Hoe voorkom je dat gebruikers verdwalen in te veel labels? Wat betekent labeling voor Teams, SharePoint, Data Lifecycle Management en Microsoft 365 Copilot? En waarom gedraagt het platform zich soms nét anders dan je verwacht? Tijdens deze interactieve sessie deel ik mijn praktijkervaringen met sensitivity labels: keuzes die goed uitpakten, dingen die ik achteraf anders zou doen en de frustraties die je alleen tegenkomt wanneer je labels écht gaat gebruiken in productie. Dit is nadrukkelijk geen theoretische sessie. Neem je eigen ervaringen, uitdagingen en meningen mee, zodat we samen praktijklessen kunnen uitwisselen en ontdekken hoe we sensitivity labels effectiever kunnen inzetten. **Jeroen Bijdevier - Je omgeving op orde voor veilig en optimaal Copilot gebruik** Copilot ziet het verschil tussen achterhaalde en recente informatie niet. Die zal je dus een beetje moeten helpen. Rechten zijn vaak niet (in detail) op orde. Manueel deze zaken vinden is lastig en tijdrovend. Natuurlijk wil je rapportages hebben van het gebruik. Ergo dataveiligheid op orde en inzicht in het gebruik met Purview.

Welcome to the event page of the Walk & Talk in Arnhem Sonsbeekpark, taking place on Sunday March 29th, 2026. This event is a informal walk where we will connect again and perhaps meet some new people. It will be the first day of Daylight Saving Time and, fortuitously, *Zeldzaam Mooi Markt* is taking place in Sonsbeek. We plan to make a stopover here. Our event is free and open for everyone to join, including Dutch and internationals. **Practical information** \- The meetup of this walk is at **13:00 at Arnhem station, near Burger King**. We’ll start walking after 10 minutes. \- A walk like this is at a casual pace and usually takes about 2 hours\, including breaks\. We are focusing on an area\, not a specific route\. This gives us some room for suggestions of participants like when to have a few minute break\. \- We will take a coffee break at a café in between or afterwards if there's enough interest\. \- B\-YOU: Bring your own umbrella\, in case of rain\. If the weather is really unacceptable we will go to a café instead\, or cancel the entire event\. \- You can leave at any time you like\. **Sign up via Meetup OR E-mail** Please sign up for this event by RSVP on Meetup OR send an e-mail to **[urbanarnhem@gmail.com](urbanarnhem@gmail.com)** . Joining the event is free, but donations will be very appreciated. We are making costs to keep this group active on Meetup, so any (small) donation will go directly to keeping our page online. We hope to see you on this walk! \*\*\* **Disclaimers** \*SOCIAL MEDIA We might upload some of our photos and videos on social media. If you don't want to be recognized, please let us know. Our Instagram is: [@urbanrural.arnhem](www.instagram.com/urbanrural.arnhem) \*RESPECT & SAFETY Everyone partaking in the event must be treated with respect, and safety is being highly prioritized. Anyone violating this can and will be required to leave. Please contact the organizer if you feel something is wrong.

🏔️ Everest Update for the Veluwe Power Hikers We were preparing for a classic VPH high altitude expedition on top of the world. Unfortunately there is some disappointing news. Starting in 2026, Nepal is introducing strict new regulations for climbing Mount Everest. Climbers will now need to have previously summited a 7,000 meter peak in Nepal and must also submit mandatory health certificates. Because we cannot realistically summit a 7,000 meter peak and then climb Everest on the same day during our hike, I am unfortunately obliged to change the program. There is also another small complication. 1 April falls on a Wednesday, which makes organizing the expedition a bit difficult. After a poll in the WhatsApp group, we decided to move the date to **28 March** and climb the highest point of the Veluwe, **Signaal Imbosch (110 m)**. Even if it’s not Everest, don’t underestimate this hike: we will cover **22 km with about 350 metres of elevation gain** at a brisk pace. At this altitude, however, oxygen bottles are no longer recommended. Please update your RSVP if you can no longer attend due to the change. ⛰️🥾 **When and Where to Meet?** 10:10 sharp at Rheden Trainstation. ⏰ Please arrive on time, as we won’t be able to wait for latecomers. 🥾✨ https://maps.app.goo.gl/VaEtswyBps5awMoL7 **Where and When Shall We Rest?** We’ll take 2 breaks: * Lunch break in nature at Signaal Imbosch (110 m) with group photo on summit; 20 min * Snack and drink at Basecamp (80 m) where you can buy drinks and snacks; 30 min **Notifications:** * Technical equipment: avalanche transceiver (beacon), avalanche probe, and avalanche shovel (if you have them) * A compact lunch and water to share at the summit * The hike will only be canceled in case of severe avalanche risk (code 5). * If you plan to bring a companion, please ensure that they are also registered for the hike. * To be the first to get updates on new hikes, join our WhatsApp group! Feel free to ask for the QR code during the hike to easily join. * T-shirts are now available for €25, made from Fairwear-certified organic cotton with eco-friendly inks—sustainable, odor-resistant, and perfect for your hiking adventures (limited stock, available during the hike)! Let me know your size and I will bring one for you!

Een wandeling voor vaders die het zichzelf gunnen om even te willen uitwaaien én de diepte in willen. We lopen samen door de natuur, ontmoeten elkaar en delen wat er echt speelt — als vader, als man, in je werk of gewoon in je hoofd. Niets moet. Er is geen afleiding, alles draait om verbinden en inspireren. Onderweg doen we een aantal oefeningen, luisteren we naar elkaar en stellen we de vragen die er toe doen. Een ideaal moment om even tot jezelf te komen — die ontspanning neem je sowieso mee naar huis. **Past dit bij jou?** Je hoeft geen antwoorden te hebben. Alleen de bereidheid om eerlijk te zijn — naar jezelf en naar de andere vaders om je heen. **Wat kun je verwachten?** * Een kleine groep van max. 8 vaders * Een mooie route op de Veluwe * Goede gesprekken en oefeningen onderweg * Ruimte voor jouw verhaal * Koffie/thee en een snack na afloop Kortom: een wandeling waarmee je investeert in jezelf en je vaderschap. duur: 10:00-12:00 uur / investering: €20 locatie: rondom Arnhem op de Veluwe

Builders, creators, architects, admins, consultants - come one, come all. This one's for you. We're bringing a little friendly competition to the Columbus ServiceNow community while highlighting the cool things people have built on the platform. Five presenters will take the stage to showcase something they've built, solved, designed, or imagined on the ServiceNow platform - and a panel of judges (plus YOU, our amazing audience) will score them live. So basically, America's Got Talent but make it ServiceNow's Got Talent. Bring a notepad if you'd like 'cause you'll definitely be learning something new. Each presenter gets 10 minutes max to wow the crowd with: • A demo • A real-world business solution • A bold idea • A UX transformation • Or a creative use of the platform Judging Criteria: 🏆 Business Value 🚀 Innovation ✨ User Experience This event is about celebrating ideas, sharing knowledge, and showing how ServiceNow can drive both business impact and meaningful user value. Come learn. Come support. Come get inspired. Refreshments and bites will be provided. And maybe next time… you’ll be on stage.

Want to be a speaker? submit your talk to our Call for Presenters!!! https://sessionize.com/cbus-hug-2026/

**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 **Abstract** Web Forms gave .NET developers a powerful abstraction for building reusable UI controls long before design systems were a thing. Web Components finally bring that same idea to the browser natively. This session explores how the Web Forms mindset translates into Custom Elements, Shadow DOM, and HTML templates. We’ll examine how Web Components enable design systems that work across frameworks, how they differ from server‑driven controls, and why they’re becoming a foundational layer for modern UI. Whether you’re maintaining legacy apps or building greenfield projects, you’ll leave with a practical understanding of how to apply familiar patterns in a modern, standards‑based way. **YouTube Link** TBA

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.

**First meetup of the Columbus AI Engineering group.** We’ll kick things off with a practical, beginner-friendly discussion on: **How LLMs like ChatGPT actually work — and how to build real applications with them.** We’ll cover: * what’s actually happening under the hood (at a high level) * why LLMs behave the way they do (hallucinations, prompt sensitivity, etc.) * how people are building real systems with them today * where things break in practice This will be a **short, informal talk (\~15–20 min)** followed by open discussion and Q&A. Whether you’re an engineer, builder, or just curious about how modern AI systems work, you’re welcome to join. No slides, no fluff — just real conversation about real systems. We’ll hang out afterward and get to know each other.

Come chat about Atlassian tools and best practices at the Nationwide Sunny Street Cafe and Breakfast is on Atlassian! Let's get the day started off with breakfast with your ACE Leaders! We're always excited to talk about Atlassian Products, share our knowledge and hand out swag! Come chat with us about new product news and anything you are working on within the Atlassian product stack. This is a great opportunity to come see what we are all about, hear new business news and share with other Atlassian users your questions and experiences. We'd love to see new and old friends come out to chat and learn about Atlassian! Agenda --- Moderators Kimberly Deal - Columbus Atlassian User Group Leader Kevin Stanley - Columbus Atlassian User Group Leader Hosted By Kimberly Deal, Atlassian User Group Leader Kevin Stanley, Chief Everything Greg Sprowls, Agility Lead --- Global Partner Atlassian (http://atlassian.com) Millions of users globally rely on Atlassian products every day for improving software development, project management, collaboration, and code quality. Partner Atlassian --- For over a decade, Atlassian customers have come together to network, share ideas, solve problems, and find new ways to use Atlassian products. Today, more than 15,000 people take part in Atlassian community events in more than 30 countries. --- Complete your event RSVP here: https://ace.atlassian.com/events/details/atlassian-columbus-presents-rise-and-shine-with-atlassian-downtownnationwide-22/.