Technology

The longest day of the year is comming and let's another Kotlin meetup. This time we geather at N26! **⚠️⚠️⚠️ Due to a venue policy please submit the following form for additional details. Without it, you won't be allowed inside the venue:** https://forms.gle/XjqVXkD3FARCM6jA8 **Line-Up:** 👉 **TestBalloon: Kotlin testing is easier (and more fun) than you think** *by Oliver Okrongli* You want an easier way to write tests? Parameterize tests in plain Kotlin? Reuse a series of tests? Easily extend own your test setup? Have first-class support on all platforms? All without struggling with a huge framework API? TestBalloon is a new test framework that brings the power of Kotlin to your test setup. With a small-surface API, a hierarchical test structure and an extensible DSL, TestBalloon makes Kotlin testing easy, even at scale. Oliver, the author of TestBalloon, will show testing patterns and strategies and lots of practical examples, ranging from simple unit tests with less boilerplate to advanced testing with coroutines and generated data. This talk is based on insights first presented at KotlinConf 2026 in Munich. At the end of this talk, you’ll be able to firmly the answer the question: "How can I master Kotlin testing with ease, and make my team release with joy and confidence, every time?" 👉 **One Topic to Rule 'Em All** *by Yonatan Karp-Rudin* Kafka delivered every event exactly once, in order, and lost nothing. So what broke? This talk follows that question into the gap most event-driven systems leave open: what actually guarantees the order your domain depends on, and what quietly doesn't. We start from a real log line, find the crack in an architecture that looks clean and ships fast, and rule out the fix everyone reaches for first. The cure turns out to be one sentence of domain thinking plus one line of config, though the Schema Registry will fight you on the way there. A live demo runs the bug and the fix back to back: same load, same hero, one change. If you build with Kafka, you have probably shipped a version of this bug. You will leave able to spot it and fix it before it pages someone. 👉 **TBD** **Speaker Bios:** 🗣 Oliver Okrongli Oliver has been shaping and creating software from backend to frontends. He is the author of TestBalloon, a next-generation Kotlin test framework. Before, he has helped to maintain Kotest, and contributed to several libraries of the Kotlin ecosystem as well as the Kotlin compiler. Can be found on GitHub (OliverO2) and the kotlinlang Slack (Oliver O). When not developing, he is most probably in deep talks, dancing, snowboarding or F18 catamaran sailing whenever he gets a chance. 🗣 Yonatan Karp-Rudin Yonatan Karp-Rudin is a Staff Engineer at Billie, building event-driven systems in Kotlin and Spring Boot. Off the clock, he plays with AI agents and builds random tooling, trying to hand off as much of his own workflow to a machine as he can. The rest of the time he's brewing mead or deep in a video game. **🗣 TBD**

We are happy to invite you to our next iOS meetup. This time we cooperate with the amazing 42 Berlin to share the knowledge and experience in iOS development. 18:00 Doors open 18:30 Welcome on campus **18:45** **— Sebastian Hagedorn, director of Engineering at Clue, presents "The Sensitive App".** Is your app really working, or just not crashing? “The Sensitive App” reports subtle bugs regardless of origin, and validates your assumptions in production so you don’t have to resort to guessing or praying. Learn how to turn your app into the first line of defense for your entire system’s health! **19:45** **— Dmitry Kurkin, lead Mobile Engineer at SuperNext, presents "Lessons that iOS Native Project could learn from ReactNative in agentic development".** We'll inspect the components of the React Native engine that provide faster feedback and boost agentic iterations.

🌟 Join us for **"Don't Eat Alone"** – an event designed to transform your lunch break into a social feast! **Tired of solitary meals in front of the computer?** **Thriving to meet some new people and curious what it may bring to your life?** Just come, check and enjoy a delicious meal with friendly faces. Connect with like-minded individuals, engage in conversations, and make your lunchtime a memorable social experience. Mark your calendar, bring your appetite, and let's build connections, one meal at a time! 🍽️🤝✨ PAYMENTS: the meetup is free, but everyone pays for their meals. Here you can pay by card easily.

Please reserve your spot by registering on the below link : https://www.eventbrite.com/e/join-biggest-community-investors-founders-berlin-online-tickets-1988380688164?aff=meetup QUESTIONS ? Pls Reach out to; Rose - +971528033410 ( WhatsApp Only)

**DRAWING AND PAINTING CLASS** **on VARIOUS TECHNIQUES** ***SUITABLE FOR BEGINNERS*** with Travis Hendrix [BOOK IT HERE](https://berlinschoolofdrawing.weebly.com/booking---contact--venue.html) Weekly on Thursdays from 7.30 to 9.30 p.m. \- to be joined anytime\! FROM THU MAY 7TH to JULY 23rd 2026 Join anytime! *Scroll down for detailed program* Pricing options: \- 4 entrances/€110 \- to be used within 7 weeks from purchasing \- Special 3 MONTHS booking: €290 \- one time drop in: 36€ This is an ongoing class from MAY to JULY 2026 The subscription to the class can be done monthly ( the 4 entrances don't have to be used in a row ) Plus: SPECIAL Price for booking 3 MONTHS to be followed in a row Each individual will be guided separately so any level is welcome! **ALL MATERIAL WILL BE PROVIDED by us:** however you are more than welcome to bring your own material and try things out. The aim of the class is to target a big range of people who know nothing about drawing, to the ones who have some experience already and want to develop ideas, techniques etc. therefore it will be suitable for complete beginners or intermediates. We will sometimes have models, sometimes work on still life, sometimes on botany, sometimes we will focus rather on techniques and some other times it ́s more liberated and free. The goal of the class is to learn how to draw, and how to find your own style with time. **DETAILED PROGRAM:** MAY 7th to JULY 30th 2026 May 7: Introduction to drawing with pencil forms, volume, perspective and shading. May 14: Drawing with pen and ink still life, focusing on positive and negative space and silhouette drawing. May 21: life drawing session with model, elaborating on pencil and charcoal and pen skills, learning about figure drawing, and applying the previous sessions into body forms and shades May 28: Drawing the face with pencils June 4: Intro to Acrylics. Materials and techniques. June 11: Colour theory applied through all painting mediums. June 18: Abstract surrealism in acrylics. How to start a painting against the fear of the blank. June 25: Image transfer with acrylic mediums and mixed media. July 2: Intro to watercolour and gouache July 9: Botanical art (drawing and painting). July 16: Introduction to Indian(Chinese) ink, learning how to work with shadows, layers and lines July23: Mixed media painting July 30: life drawing with Model, material choice up-to students ***

Join us for the first meetup 100% dedicated to agentic analytics in Berlin. **The goal:** share real-world feedback between data teams on implementing analytics agents. **The format:** a roundtable with 4 data teams who have tested or deployed analytics agents using different solutions - Cortex, Dust, Hex, nao, Omni, Looker, or in-house tools. **[RSVP on Luma.](https://luma.com/ly17mjtj)** 📣 **Speakers of the night:** * [Marina Ariamnova](https://www.linkedin.com/in/marina-ariamnova/?utm_source=luma), Analytics Manager at SumUp - LangChain vs Dust * [Andrey Pushvintsev](https://www.linkedin.com/in/pushvintsev/?utm_source=luma), Staff Analyst at Miro - Claude + custom BI MCP * [Marielle Dado](https://www.linkedin.com/in/marielledado/?utm_source=luma), Senior Analytics Engineer at CarOnSale - Dataleap, Langdock, Claude + Snowflake Cortex MCP vs Secoda AI * [Andre Wagner](https://www.linkedin.com/in/andre-wagner/?utm_source=luma), Director of Data Analytics at Taxfix - Claude + custom plugin vs Looker The panel will be moderated by [Christophe Blefari](https://www.linkedin.com/in/christopheblefari/?utm_source=luma), founder of [nao Labs](https://getnao.io/?utm_source=luma). **Agenda** 6:30 PM: Doors open 7:00-8:00 PM: Roundtable 8:00-10:00 PM: Drinks and Networking **About our sponsor:** [nao Labs](https://getnao.io/?utm_source=luma) helps teams build and operate AI coworkers for analytics and operations. Their platform focuses on practical, production-ready agent workflows so companies can turn LLM capabilities into measurable business outcomes. **About our host:** [Trawa](https://trawa.energy/?utm_source=luma) is a Berlin-based energy platform helping businesses access cleaner and more cost-efficient electricity. By combining software, data, and energy market expertise, trawa enables companies to optimize procurement and better manage energy costs. Want updates or more info? Subscribe to our newsletter: [databerlin.substack.com](https://databerlin.substack.com) Follow us on LinkedIn: [Data Berlin on LinkedIn](https://www.linkedin.com/company/data-berlin/?utm_source=luma) Looking for a job? [databerlin.net/jobs](https://databerlin.net/jobs) Join our Slack community: [Data Berlin Slack](https://join.slack.com/t/databerlin/shared_invite/zt-2q6j9x0z8-~sG7o3Q8S2j4j5gXg2yHlw)

At OpenSpace Networthing entrepreneurs from diverse disciplines, industries and nations meet to collaboratively develop solutions for challenges presented by participants. This month we will dive deeper into building digital products with Vibe Coding & AI with Varun Jain. We are building a networking-App: The "Tinder for Entrepreneurs" If you want to offer a workshop or present a topic for our members, write an email to alejandro.wagner@mlp.de Entrance is free! Bring in your expertise instead.

The Creative Code Jam is a monthly gathering of artists, makers, designers, illustrators, coders, musicians, performers, learners and anyone interested in the use of computing skills for artistic expression. The event is free and open to all, regardless of age, origin, gender or experience. The jam is an opportunity to meet likeminded people and get creative together in a relaxed and safe environment. Beginners and first-timers should feel especially welcome! WHAT SHOULD I EXPECT? **Bring a laptop** and/or anything you’d like to work on, whether it’s a personal project, an experiment, or a skill you want to learn. You can come with friends or meet new people here. There’s no set agenda: some people code, some sketch ideas, some collaborate, and others just chat and get inspired. SCHEDULE Doors open at noon, then we’ll have quick introductions so everyone can share what they’re planning to work on. Note: arriving on time is the best way to hear what others are up to ;) Around 6 pm, we gather to share what we’ve worked on during the day. BEGINNERS WELCOME! If you’re new to creative coding, we'll be happy to help you get started, and you can find beginner-friendly resources at [creativecode.berlin/learn](http://creativecode.berlin/learn). THIS IS YOUR SPACE We do our best to create a welcoming environment for all people regardless of race, ethnicity, color, religion, gender identity, sexual orientation, national origin, age, disability, or genetics. People from group generally underrepresented in open-source, art, and technology fields are warmly encouraged to come by. And if you know someone who might enjoy this meetup but isn’t sure it’s for them, let them know they’ll be welcome! SAFE SPACE POLICY We support the Berlin Code of Conduct: https://berlincodeofconduct.org/ Please make sure you agree with its content. ABOUT MotionLab.Berlin MotionLab.Berlin is Germany’s premier Innovation Hub & Makerspace – an ecosystem for Hardtech, art, creativity, and entrepreneurship. They are an international community with access to state-of-the-art machinery, prototyping machines, coworking spaces, offices, and production facilities. More info: https://motionlab.berlin/ ACCESSIBILITY MotionLab is located on the ground floor, with bathrooms on that same level, although unfortunately they are too small for wheelchairs. FOOD MotionLab has drinks and snacks for sale. Bio food can be found on LPG at Bouchéstr (\~200m). Their cantine has vegan, vegetarian and other food options until 8pm. DO I NEED TO SPEAK GERMAN? We speak mostly English so international guests are more than welcome! Our team also speaks French, Turkish, Italian, Spanish, Dutch, Finnish and German... though language availability may vary depending on which organizers are present :) CONTACT Raphaël de Courville team@creativecode.berlin +49 176 700 70572 or get in touch via [creativecode.berlin](https://creativecode.berlin/)

Welcome to Sunday Tech Coffee. This is a **networking** event for those in the tech industry in Berlin. We are usually inside and to the right. Ask the barista/bartender if you can't find us.

Join Us for a Morning Swim at Humboldthain Outdoor Pool! Hey everyone, We are doing another relaxed swim meet-up at Humboldthain outdoor swimming pool, and I'd love for you to join! We'll be gathering for a casual 30-minute swim - nothing competitive, just a chance to enjoy the water and start the day on a refreshing note. Afterwards, if you're up for it, we can go to a nearby cafe for a coffee and chat, but no pressure - totally optional! 📝 **Bring** - ID/passport (mandatory, checked by the pool staff) !!! - swimsuit - towel - 1 Euro coin (for a locker) - ticket is around €5.50 (buy online or at the pool) **RSVP** Please un-RSVP ❌ if you cannot come! Otherwise we would unnecessarily wait for people to never show up. 📍**Where** At the pool entrance (see the map pin) and wait for 15 min for people to gather. You need to enter Humboldthain park. 🎟 **Pool tickets** [https://www.berlinerbaeder.de/baeder/detail/sommerbad-humboldthain/](https://www.berlinerbaeder.de/baeder/detail/sommerbad-humboldthain/) ☕ **Coffee** A wonderful coffee shop a few minutes away from the pool [https://maps.app.goo.gl/os3WHTSfYzbDyKQh7?g_st=ac](https://maps.app.goo.gl/os3WHTSfYzbDyKQh7?g_st=ac) Looking forward to seeing you there!

​**Founders Running Club** (FRC) brings founders, investors, tech, creative people and startup enthusiasts together for weekly easy runs and networking. ​Every Saturday morning we gather together and run through Tiergarten. Join us in one of these 3 routes: ​\* **5K** – for new & beginner runners ​\* **7K** – for regular runners ​\* **11K** – for more experienced runners **OBS**: We are usually around 30 people, between regulars and newcomers (from here and from Luma), so don't be scared if there are not a lot of people confirmed on the event here. The pace is chill and conversational, around **6:30**. On the 7k and 11k some people like to push a bit more, but no one gets left behind. We finish with a nice coffee and amazing conversations. The vibe is always great. Pets, friends, family, are welcome. More about **FRC**: ​🗓️ Launched in San Francisco, July 16, 2022 🌍 Now in 50+ cities 📅 Running + Networking events + Community ​**Join the community** [http://foundersrc.com/chats](http://foundersrc.com/chats?utm_source=luma) Berlin Instagram [http://instagram.com/frcberlin](http://instagram.com/frcberlin?utm_source=luma) ​ **Global FRC**: Instagram [http://instagram.com/foundersrc/](http://instagram.com/foundersrc/?utm_source=luma) LinkedIn [http://linkedin.com/company/foundersrc/](http://linkedin.com/company/foundersrc/?utm_source=luma) Strava [http://strava.com/clubs/foundersRC](http://strava.com/clubs/foundersRC?utm_source=luma) Website [http://foundersrc.com/](http://foundersrc.com/?utm_source=luma)

**Nerds, Creatives & Dreamers** is a small, curated gathering in Berlin for two kinds of people who almost never end up in the same room: the ones who build things with code, and the ones who build things with imagination. Developers and painters. Engineers and writers. Founders and photographers. In daily life these worlds rarely collide — here, that collision is the whole point. Just a good space, a deliberate mix of curious people, and the freedom to let the evening unfold. Come ready to be surprised by who you meet and where the evening takes you. A room full of curious humans. We’re here to socialize as human beings. And if you do exchange contacts — make it personal, not transactional. **🛠 If You Build Things** · Developers & Engineers · Designers & Product People · Founders · People Who Code for Fun **🎨 If You Create Things** · Writers & Journalists · Photographers · Artists & Painters · Anyone With a Side Obsession 👉 **You can also join via Luma if this event reaches capacity: https://luma.com/0y2yd2q4** Please RSVP “yes” only if you can make it, so we can save a seat for you and others on the waitlist. **📝 Note:** You are welcome to attend our social meetup! The event is free. The space is generously hosted for us — the only thing we ask is that you support it by buying a drink, etc. A small gesture that keeps evenings like this possible. **🤝 Community:** This is a space built on curiosity and respect. We keep it that way — for everyone.

Unser Verein berlinCreators e.V. trifft sich jeden Freitag ab 18 Uhr im Makerspace. Wir haben Gruppen rund um Elektronik, 3D-Druck, Nähen, Programmieren, Retro Computer. Egal ob Anfänger oder Profi – hier seid Ihr Willkommen. Ihr könnt mit anderen fachsimpeln, Euch inspirieren lassen oder auch mit unserer Hilfe Eure ersten Projekte starten. Wenn Ihr Euch bei uns wohlfühlt und Mitglieder bei den berlinCreators werden möchtest, freuen wir uns. Kommt vorbei, lernt den Space, uns und die Möglichkeiten kennen.

## 🤝 Host Information A co-hosted event by ProductTank Columbus & Women in Product Columbus 💡 About the Workshop AI adoption is stalling across organizations — not because of a lack of motivation or tools, but because it's fundamentally a behavior design challenge. This hands-on workshop applies proven Behavior Design models and methods to help you move from a vague organizational wish to boost AI adoption to 3-5 concrete, testable interventions you can act on starting tomorrow. Whether you're a product manager, on a product team, or just someone trying to get AI to actually stick at work, you'll leave with a clear picture of what's worth focusing on, what to ignore, and how to drive real, sustained adoption — no guesswork required. 🛠️ What to Bring Laptop: Fully charged and ready to go. AI Assistant: Have your favorite AI assistant pulled up. (Dom will be using Claude, but feel free to use whichever assistant you prefer!) 🍕 Logistics & Perks Food & Drink: Pizza and drinks provided! Parking: Plenty of free spaces available on-site. ###

We are bringing Microsoft Build sessions to Columbus Ohio! The Central Ohio Azure Meetup and Central Ohio .NET Developer's Group (CONDG) are coming together to bring some of the labs and breakouts from Microsoft Build to your backyard. In this free, 1 day event, you are going to Build stuff with us! And yes, there will be free food. Please RSVP via [Microsoft Build //localhost:columbus | Microsoft Reactor](https://developer.microsoft.com/en-us/reactor/events/27247/).

Most people still use AI like a search box: type one question, get one answer, repeat. But the next step is AI agents: systems that can take a goal, break it into steps, use tools, remember context, and produce useful work for a human to review. In this beginner-friendly session, we’ll demystify what AI agents actually are — without hype or jargon. We’ll walk through practical examples of how agents can help with research, planning, writing, coding, operations, and personal productivity. We’ll cover: * What makes an AI “agent” instead of just a chatbot * How agents break tasks into steps * Where agents are genuinely useful today * Where they fail, hallucinate, or need human review * How to design simple AI workflows for your own work * A live demo of an AI agent-style workflow from start to finish No coding experience required. This is for anyone who wants to understand where AI tools are going and how to use them more effectively right now. LOGISTICS AND PARKING: The talk starts at 7:00 PM. The first half hour is reserved for everyone to get set up and mingle. Free pizza and drinks! The cheapest parking option is to find street parking, which will only cost you a few bucks. Otherwise, park in the nearby veteran's museum lot for $8. It's highly recommended you avoid the nearby $15 garage parking.

We're going to GameArena! We'll be in-person at the GameArena Gateway for our monthly COGG Prototype and Play event. Come to play and showcase your games! We're back in the upper levels of the catwalk area. It'll be packed with lots of camaraderie playing your game(s) and other's games on the 2nd floor. Light snacks and water provided but you can buy food and drinks at the bar (alcoholic drink ID required). [www.game-arena.co](http://www.game-arena.co/) **Attendees:** Don't have a game to show? Not a problem! All are welcomed and invited from all ages and backgrounds. The more we can have to play test our games is all the better! **Developers:** Do you have a game that you would like to get critical feedback on? Would you like an excuse to work on a game with other talented artists, programmers, musicians, designers, and writers? Digital, table-top, non-experienced developers, and the like are welcomed! We'll provide signage for your game to help others learn more about your work. Wifi, outlets, tables, and seats (though standing tables also) are available. Come to the Prototype and Play workshop to collaborate and meet local game developers for an evening of epic and raw game play fun! Play works-in-progress, show off your own game, work with others to add polish to a game, or even lend your talents to other fellow developers. For this event, light snacks from the bar and water will be provided! Though you can purchase you own if you like at the bar: [https://www.game-arena.co/menu](https://www.game-arena.co/menu) Can use South Garage at the Gateway with a $5 voucher on your way out. 75 E 11th Ave, Columbus, OH 43201 [https://maps.app.goo.gl/UwgveUYG37Jy7RtS9](https://maps.app.goo.gl/UwgveUYG37Jy7RtS9) If you have any questions or comments, as always, feel free to reach out to us at [info@thecogg.com!](http://info@thecogg.com!/)

Let's get together and listen to **[Eric Rico](https://www.linkedin.com/in/ericrico/)** from Unity3D (title TBD). Eric also runs the **[Columbus Unity User Group](https://www.meetup.com/columbus-unity-user-group/)**. Check it out! ***Bring your laptop and expect to write some (non-AI-generated) code!*** *(title subject to change)* Food and drinks will be available. **LOCATION:** 6515 Longshore Loop, Suite 300, Dublin, OH 43017 **FREE PARKING:** 6725 Longshore Street, Dublin, OH 43017

Topic to be announced. **CALL FOR SPEAKERS** Learn more: 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/ **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

**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** *July Meeting - Lightning Talks!* Lightning talks are very short presentations on a topic of your choice (must be related to .NET). Talks should be 15-20 minutes in length and include minimal slides and quick demo (no live coding please). There will be 6 slots available! First come, first serve! **YouTube Link** TBD