Trail Running

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)

**Um was geht es dieses mal?** **Das Ende der Code-Ära: Warum Domain Modeling & Harness Engineering die wichtigsten Skills 2026 sind. - Benjamin Font Pera (codecentric)** "Die Ära, in der Softwareentwicklung primär durch das Beherrschen von Programmiersprachen und Frameworks definiert wurde, ist vorbei. Wer 2026 noch versucht, über reine Syntax-Kenntnisse Wertschöpfung zu generieren, hat gegen agentische KI-Systeme bereits verloren. Die eigentliche Herausforderung hat sich nach links verschoben: in die präzise Definition von Problemen und die Konstruktion von Leitplanken. In diesem Talk räume ich mit dem Mythos auf, dass KI uns das Denken abnimmt. Im Gegenteil: Die Verantwortung steigt. Ich stelle das Konzept des Harness Engineering vor – die Kunst, fachliche Anforderungen so in Test- und Evaluationsgerüste zu gießen, dass KI-Systeme darin verlässlich operieren können. Als Agentic Coding Engineer und AI Coach zeige ich auf, warum Fachlichkeit zur wichtigsten technischen Fähigkeit wird. Wenn die KI Code generiert oder “halluziniert”, ist das tiefe Verständnis der Domäne das einzige verlässliche Werkzeug zur Qualitätssicherung. Die Kernbotschaften: Problem-Definition als Hard-Skill: Warum die Fähigkeit, komplexe Fachlichkeit präzise einzufangen, das neue „Clean Code” ist. Harness Engineering statt Code-Fixing: Wie wir die Kontrolle behalten, indem wir das „Harnisch” (Evals & Guardrails) bauen, statt Zeile für Zeile zu reviewen. Shift Left zur Domäne: Warum Entwickler:innen 2026 mehr wie System-Architekten und Domänen-Experten denken müssen, um relevant zu bleiben. Lessons Learned vom AI Coach: Warum die größten Hürden dieser Transformation nicht technischer Natur sind, sondern im Mindset der „Lösungs-Produzenten” liegen. Dieser Vortrag ist ein Weckruf für alle, die Softwareentwicklung noch als Handwerk am Code verstehen – und ein Leitfaden für diejenigen, die bereit sind, die nächste Ebene der Abstraktion zu besetzen." **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)

Is public speaking something you’ve always wanted to learn? Then you’ve come to the right place! Experience a safe and playful environment at U-Speak Toastmasters where you can develop your public speaking, communication, and leadership skills! ## **Welcome to U-Speak! Toastmasters** Join our vibrant community at U-Speak!, where internationals and Dutch locals from Utrecht and its surroundings come together. U-speak! Toastmasters is a welcoming, safe, supportive and playful environment where you can work on your public speaking, communication and leadership skills! ## **Discover our meeting experience** Curious about what happens during our meetings? Here’s a glimpse into a typical evening at U-Speak! Our gatherings feature a lineup of three prepared speeches, engaging evaluations and impromptu speaking sessions. At U-Speak!, every member gets their chance to shine. Whether you’re delivering a speech, providing feedback, or stepping up for impromptu speaking, our supportive environment ensures that everyone’s voice is heard and valued. * ⏰ Time: 19:15 - 21:30 (7.15pm to 9.30pm) Walkin at 19:15; Start of the meeting at 19:30 * 🌐 Venue: Room 8, Top Floor, Pub Florin, Utrecht * 🙋🙋‍♂️🙋‍♀️Attendance: Typically, 15-20 people attend each meeting Many of our club members are not on Meetup, so the number of people attending as indicated here is not reflective of the actual number of people attending on a night. * 🙋🙋‍♂️🙋‍♀️ Guests are welcome; rsvp is encouraged

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.

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

Our sister company FrontValue is organizing a great meetup which might be of interest for you as well! Same location as you're used to. **RSVP via** https://www.meetup.com/frontvalue/events/314972778/ We are back with two great speakers! 💡 First on stage is **Bart Waardenburg**, the creator of the tool **Fallow.** His tool gained significant traction after it was discussed on the web development podcast Syntax. **Vibe Coding Doesn't Scale: Deterministic Tooling for Agentic Engineering** *AI Slop Is a Tooling Problem* Most AI coding fails in the same way. The model writes plausible code, but it has no deterministic way to check whether the change made the codebase better or worse. We compensate with prompts like "make no mistakes", "follow best practices", or "act like a senior engineer". In his talk, Bart shows where the line runs between AI slop and real agentic engineering. Using Fallow as the case study, he walks through how an agent calls deterministic codebase-quality checks through CLI, MCP, and agent hooks, so engineering standards live in the loop itself instead of in wishful prompts. The agent generates code, inspects the repository, detects dead code, duplication, complexity hotspots, and boundary violations, optionally combines that with runtime evidence, and uses those signals to refactor or self-correct before a human reviews the diff. The core idea is simple. The biggest productivity gains do not come from telling the model to be smarter. They come from giving it a better harness. For frontend teams, that is the difference between vibe coding and scalable, reviewable engineering. [https://fallow.tools/](https://fallow.tools/) 💡 After the break, we welcome **Sander van Surksum** on stage. Sander is a web performance specialist who works with global brands to build fast, stable and world-class digital experiences. **Vibe coding made the web sick. Now it can fix it.** Since ChatGPT went live in November 2022, the median mobile web page has been getting heavier three times as fast as before. AI didn't invent bloated front-end code; it learned from a "lost decade" of bad patterns and industrialized them. Sander follows the evidence: the public HTTPArchive data that marks the inflection point, and Alex Russell's *Performance Inequality Gap*, which asks the question most teams never do — **whose device are we actually testing on**? Spoiler: the bill isn't paid by the developer on a MacBook Pro and fibre. It's paid by the user on a €300 Android, 9 Mbps. The same code, two completely different realities. Today's median page is already bigger than the entire game DOOM. The talk ends with good news. The same AI that made the mess can help clean it up, once you give it eyes. We'll look at the 2025–2026 tooling (Chrome DevTools MCP, Google's Modern Web Guidance) that finally lets AI agents measure real performance and ship lighter code, and close on the one question every engineer should answer before their next prompt: **who are you building for**? **📍 Location** We welcome you to our office in Utrecht: Studio N in the Werkspoorkathedraal. The address is Tractieweg 41. We have plenty of free parking space available. We will have dinner ready for you at 18.00! **🕔 Agenda** **18:00** Walk in & food **18:30** First talk **19:30** Break **20:00** Second talk **21:00** Drinks & Bites Both talks are in English. RSVP now for an evening of learning and fun. Don't miss out on this amazing opportunity to learn and connect with our community of frontend developers!

Join the Dutch Outdoor and Hiking Group for a day hike and enjoy Beautiful shell path along the Lower Rhine and visiting De blauwe Kamer and hiking on the Grebbeberg * We **start at 11:00** from the train station in Rhenen https://maps.app.goo.gl/CrbeFtQPutUSYWFp7 * Length: \~18 km (4 - 5 hr hiking) * What to bring: lunch, water, snack. * For whom: As always, sporty folks that like to combine social event with being active in nature. **Getting there by Train:** * To train station in Rhenen. https://maps.app.goo.gl/CrbeFtQPutUSYWFp7 **Getting there by Car:** * Free Parking: Stationsplein, 3911 AP Rhenen https://maps.app.goo.gl/qVrH9pA5JK2prQPg9 **Note:** * Please **pay a small fee (3 euro)** to help us cover the (increased) yearly Meetup contribution of 240 euro. We'll ask you to pay before the start of the hike (can be on the day itself). No refunds, but in the unlikely event that hike would be cancelled and you already paid, you don't need to pay for your next hike. Thank you so much! Use the **safe link** here: https://www.ing.nl/payreq/m/?trxid=WrVKENccZiV4tdRSPrVbFG4WVyikUVQn * Keep in mind that the hike can be canceled when the weather is very bad (**always check the event before you go**). * If you RSVP 'yes' we expect you to show-up. Please do not cancel less than 24 hours before the hike. **No-shows** will lead to your removal from the group. Thanks for the understanding. * By signing up for this event, you agree to release the organizers from any responsibility and liability in all claims. As the participation is strictly voluntary and you freely choose to join, it is the responsibility of individuals participating to ensure that they are fit enough and have adequate coverage to protect themselves.

Who says games are just for kids? Remember playing games when you're a kid with no need for a manual and no responsibiliies? That's what we're doing. Tag, Cops and Robbers, Ninja... Stir up the memories of what made you happy and bring that pure joy out. Sign up through this [1 question form.](https://forms.gle/XWHNG63iyzuumEon8) To make our inner child completely satisfied, we'll reward ourselves with a hangout and pancakes at Teahouse Rhijnauwen after! 💵 Price : Free 👝What to bring: water, sunscreen, comfortable shoes, an open mindset

Bakery Walk: A Sunday Girls Stroll Let’s romanticize our Sundays in Amsterdam. ☕🥐 We’ll meet and start with a relaxed city walk for coffee & pastries. Between stops, we’ll: ✨ Mix & match conversation buddies ✨ Use fun conversation cards (no awkward small talk) ✨ Get our steps in (pastries taste better after walking 😉) Perfect for new expats and women looking to build genuine friendships in Amsterdam. Come solo. Leave with new connections Please note: everyone buys their own pastries & drinks at the bakeries. That way you can pick what you like best! **Join our WhatsApp group💕** https://chat.whatsapp.com/JFgvbHvRLoP5P9K3GtwGlU?mode=gi_t

I'm excited to host the 24st edition of *Strangers to Friends*! Every event so far has been warm, fun and full of great connections. So we’re doing it again! Curious about our previous events? Check out our photo albums (only visible on the laptop version of Meetup). **What to expect** * A safe, relaxed environment to meet both locals and expats, whether you want to meet new people, experience an international atmosphere or talk about business, it’s all possible. * Start the evening with a few rounds of conversation cards: pair up with someone you don’t know, answer meaningful questions and rotate every 10 minutes. Within just one hour, you’ll get to know several people really well and enjoy meaningful conversations. * Everyone comes on their own, so it’s easy to connect. **Practical details** * Doors open at 20:00, after 30 minutes we start with conversation cards * Venue: Boekencafé Libertas, Klarendalseweg 477-1, Arnhem * 20 min walk from Arnhem Central * 7 min walk from Arnhem Velperpoort * You’ll receive 1 drink token for (beer/wine/soft drinks) and snacks all night! * Find us on the right side of the café at the bar, by the window and garden Bring a smile and join us for an evening where friendships grow, business ideas spark and real-life connections happen. Back to basics, away from screens, meeting face-to-face. Warm regards, Julia

For the first time ever, we, as Outdoors in Utrecht, will be undertaking a walkathon for a good cause Stichting Hartekind is a non-profit charity organization (and the only one in NL) that provides funding for scientific medical research for heart diseases affecting children (0-15 years) https://www.hartekind.nl/ We will be hiking the entirety of the north dunes reserve up until Den Helder to raise awareness about the organization & its actions, plus raise funding for the organization If you want to participate, that's awesome! You can join for the full hike or part of it Starting point is Castricum train station @ 8:00 in the morning You can also join of course for part of the hike. The route & its milestones are * Start point --> Castricum train station * Eggmond aan Zee (15km) * Bergen aan Zee (10 km) * Camperduin (10 km) * Petten (10 km) * Callantsoog (10 km) * Julianadorp (10 km) * End point --> Den Helder train station (10 km) Aim is to be at Den Helder by 23:00 - 23:15 so anyone can take the last train back home to Utrecht/Amsterdam/other Our pace will be 5-6 km/hour on average. You can pace yourselves with us but, in order to achieve the full route within a day, we can't slow down and do our normal amount of breaks I recommend you stick with us, and when it gets rough you can drop out completely at a milestone point or continue at your own pace from there. I'll provide a full visual map closer to the event day if you cannot join, but still want to support, you're more than welcome & appreciated to donate for the cause Here is where you can donate Please only donate an amount you feel comfortable with, and don't financially push yourself 🙏 https://supporta.com/pp3m/fvw1d12kg4?utm_source=copy_link&utm_medium=customer&utm_campaign=fundraiser_page_share Note that this event will not be postponed, unless there's major weather warnings, or train traffic issues. Even if it rains, this event is happening I hope you join me, even in spirit, in this cause of mine Constantinos

*Please note: this meetup will be held in English.* In this first meet up, you will be shown a set of immersive artistic and design research experiments. Project Thuis conducts two years of artistic and design research into immersive experiences that place the body at the centre. The central question is: "How can immersive experiences in (semi-)public spaces contribute to a sense of connection, belonging, and 'feeling at home'? To explore this, a multidisciplinary consortium consisting of [Fillip Studios,](https://www.fillipstudios.com/) [affect lab,](https://www.affectlab.org/) [Introdans,](https://introdans.nl/) [Utrecht University,](https://www.uu.nl/staff/SPonzanesi) and the [Amsterdam University of Applied Sciences,](https://civicinteractiondesign.com/) has embarked on a creative journey together. Within the context of Project Thuis, this meetup will focus on artistic and design research forms applicable across various disciplines. **Programme:** 16:00 - 16:15: Opening 16:15 - 17:15: Interactive session 17:15 - 17:30: The role of the maker in the future of immersive experiences 17:30 - 18:00: Networking and drinks (including presence of [CIIIC](https://us2.mailchimp.com/mctx/clicks?url=https%3A%2F%2Fwww.ciiic.nl%2F&xid=f4ced03a90&uid=2313462&iid=e62065ab18&pool=cts&v=2&c=1780312609&h=0b99fb0b79b5fe3d2625a4891bea9d8bc6ef045db3b8ee6ffe56d6cfc6e501c4)) Within the context of Project Thuis, this meetup will focus on experiments that you, as a maker, can use to conduct artistic and design research across various disciplines. *[This event marks the first in a series for Project Thuis (Home). Ontwerp Platform Arnhem has been invited to organise the meetups. We strongly endorse the importance of initiatives like this, and are highly committed to connecting designers with these themes and consortia](https://www.ciiic.nl/)***[.](https://www.ciiic.nl/)**

I’m putting together a small hike trip weekend in Hoorneboegse heide in Hilversum, the idea is to come with a few people who want to step out of their routine, spend time in nature, and meet others in a relaxed way. This is not a tour or a structured retreat. The idea is simple step out of your comfort and everyday life to reconnect with nature and with each other. We will – explore the beautiful nature – share a few moments together – and keep things easy and natural There will be time together (walks and sunset). Group size will be small (around 2- 4 people), to keep it comfortable and personal. This Meetup is to connect people who are interested in real and human connection If this resonates, feel free to join and I’ll share more details 🙂

**🎉 Meet Cleveland Singles Tonight — Zoom Speed Dating** Four quick rounds, real conversations, and Cleveland singles matched to you by age and personality. All from your couch. **Here's how the night runs:** - Register and take a short personality quiz - Jump on Zoom when the event starts - Meet singles in guided one-on-one rounds - Get your mutual matches by email afterward **Choose your group and register:** → **Ages 18-32** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Cleveland&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=18-32&face_v=8.0) → **Ages 30-46** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Cleveland&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=30-46&face_v=8.0) → **Ages 40-58** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Cleveland&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=40-58&face_v=8.0) → **Ages 55+** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Cleveland&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=55+&face_v=8.0) > Important: RSVP is not the same as registering. Use your age link below and complete the quiz to secure a place. Limited capacity. Your next great conversation is one click away. 💜

Join us for a great 2 mile hike through Blendon Woods Metro Park, hiking the Sugarbush Trail. This is a largely wooded hike on a flat dirt trail with some tree roots and rocks. Please meet us at the start of the trail in the Nature Center parking lot.

**🌷 Meet Cincinnati Singles Tonight — Zoom Speed Dating** Four quick rounds, real conversations, and Cincinnati singles matched to you by age and personality. All from your couch. **Here's how the night runs:** - Register and take a short personality quiz - Jump on Zoom when the event starts - Meet singles in guided one-on-one rounds - Get your mutual matches by email afterward **Choose your group and register:** → **Ages 18-32** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Cincinnati&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=18-32&face_v=8.0) → **Ages 30-46** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Cincinnati&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=30-46&face_v=8.0) → **Ages 40-58** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Cincinnati&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=40-58&face_v=8.0) → **Ages 55+** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Cincinnati&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=55+&face_v=8.0) > Note: clicking RSVP alone won't get you in. Register via your age group and take the quiz. Places fill up. Your next great conversation is one click away. 🎉

**Hike the Scioto Audubon trail. All paved and flat!** **Plan on 3-4 miles. Hike at your own pace, no one left behind.** **Lunch after at Nocterra for those who wish.**

**💌 Live Zoom Speed Dating with Toledo Singles** No apps, no awkward bios. Just live one-on-one Zoom chats with Toledo singles picked for you. **Here's how the night runs:** - Register and take a short personality quiz - Jump on Zoom when the event starts - Meet singles in guided one-on-one rounds - Get your mutual matches by email afterward **Find your bracket and grab a seat:** → **Ages 18-32** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Toledo&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=18-32&face_v=8.0) → **Ages 30-46** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Toledo&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=30-46&face_v=8.0) → **Ages 40-58** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Toledo&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=40-58&face_v=8.0) → **Ages 55+** — [Register here](https://theliveround.com/product?productId=574&productType=onlineSpeedDating&city=Toledo&groupurlname=collective-of-adventure-map-and-trail-walkers&ar=55+&face_v=8.0) > Note: clicking RSVP alone won't get you in. Register via your age group and take the quiz. Places fill up. Register, relax, and let the night do the work. 🔥

This is a small but pretty park with a 1.7-mile loop. We will walk it 2 times. It goes along a ridge and has moderate elevation changes.