Open Source Hardware

Combinatorial optimization problems arise across logistics, scheduling, and engineering, and C++ remains a language of choice when performance matters. This lecture takes a practical look at solving such problems in C++, using the Electric Vehicle Routing Problem as a running example. We begin with an exact solver, formulating the problem as a mixed-integer program and trying to solve it through GLPK's C API directly from C++. Exact methods, however, quickly hit their limits on real-world instances. The second half of the talk turns to metaheuristics: how they are designed, why C++ is particularly well suited for implementing them, and what design choices matter most in practice. We'll walk through a concrete implementation, touching on data structures for fast neighborhood evaluation, generic algorithm design with templates, and the performance considerations that separate a prototype from a production-ready solver. The goal is not to advocate for one approach over another, but to show how C++ supports the full spectrum of optimization techniques. # About Speaker Luka Matijević is a researcher at the Mathematical Institute of the Serbian Academy of Sciences and Arts, whose work bridges academic research and freelance engineering. He's drawn to identifying the right algorithm for a given problem — and to the kind of careful optimization captured by one of his favourite Futurama lines: *"When you do things right, people won't be sure you've done anything at all."* ## 📅 Event Details | | | | --- | --- | | 👤 **Speaker** | **[Luka Matijević](https://www.linkedin.com/in/luka-matijevic/)** | | 🕕 **Date & Time** | **27th of May (Wednesday), 6 pm** | | 📍 **Location** | **Beograđanka, Vidikovac, 22nd floor** | | 🏢 **Address** | **Masarikova 5** | | 💻 **Online** | **[C++ Serbia YouTube](https://www.youtube.com/@cppserbia)** | See you!

Christians in Tech is a community at the intersection of faith and technology. Our meetups are designed to spark meaningful conversations, promote knowledge sharing, and encourage growth—both in your career and your spiritual walk with God. Whether you're an experienced professional or just starting your tech journey, CIT welcomes you. Our Website [https://linktr.ee/citcbus](https://linktr.ee/citcbus) Sponsors and Partners * Improving (Venue Sponsor) * Bethel World Prayer Center (Fiscal Sponsor) * Fruits & Roots (Coffee Partner)

PLEASE NOTE!!! This event will be In-Person for our very 1st Improving collab! If you know the [Columbus Unity group](https://www.meetup.com/columbus-unity-user-group/) location, we'll be at the same place. This is our 1st event and are doing a soft launch with limited attendance. 1st come 1st serve. If you want to be there and we fill up, please email me at [info@thecogg.com](mailto:info@thecogg.com) and I'll be in touch. All street parking is free on Sundays but you can also pay to park in any of the local garages. See image of [parking map here](https://drive.google.com/file/d/1Mr9_LFIggbs-0_Zd3AJTGNqEhgMf2TzQ/view?usp=sharing). \-\-\- On the last Sunday of the month, we're having our usual end-of-the-month social gathering with our GameDev Meetup meeting. There will be announcements and presentations followed by some social networking Let's continue the conversations with good vibes and friends. All are welcomed from all ages and backgrounds to this public event. If we can, we'll be streaming or uploading the video later via our COGG YouTube channel here: [https://www.youtube.com/@TheCOGG/streams](https://www.youtube.com/@TheCOGG/streams) (Also please do subscribe if you have not done so!) No game development experience required! If you are interested in doing a 20 minute game development related presentation, please fill out our form online here: [https://goo.gl/forms/lVdTJZiNJewlPJuj1](https://goo.gl/forms/lVdTJZiNJewlPJuj1) Or e-mail us at info@thecogg.com with the following: Your Name, Company/Affiliation, Name of Your Game/Topic, Description, Tech Needs, and Your Contact. Be sure to check out our Discord for real time news updates: [https://discord.gg/NrBhuNQ](https://discord.gg/NrBhuNQ)

Community Backyards Workshop .Community Backyards Workshop - Westerville Join us for the Westerville Community Backyards workshop! This is a FREE class on how you can protect our waterways and environment with small changes in your gardening habits. We will discuss rain barrels, rain gardens, composting, and native plants. This workshop is presented by Friends of Alum Creek. By attending, any participating community resident can receive a voucher for a rain barrel, compost bin, or native plants for attending. Vouchers are limited to one per household per year. Registration in advance is encouraged but not required. * Location: Westerville Community Center, 350 N Cleveland Ave, Westerville, OH 43082 * Date and time: Sat, May 30, 2026 10:00 AM - 11:30 AM * Organizer: Community Backyards Program, (614) 486-9613, communitybackyards@franklinswcd.org (Free Workshop Registration: Registration is free. Registering in advance provides your information to Franklin Soil and Water ahead of time, so when you come to the workshop, we will have your voucher ready for you when you arrive) https://lp.constantcontactpages.com/ev/reg/h2w5ms8 **FAQs** **Our Community Backyards workshops are FREE and a great way to participate in the rebate program. Our workshops are typically 1 to 1 and a half hours long and held in-person. Our workshops cover the same content as the online course, but they are more detailed and allow the chance to ask questions and have discussions with the presenters and other residents. We occassionally have "advanced topics" classes where you dive deeper into one topic of Community Backyards such as invasive vs. native plants or rain gardens.** **Registration is encouraged but not required.** You can register in advance to receive your voucher at the workshop. If you don't register in advance, that's okay - you can still show up (unless otherwise noted - which is very rare) and sign up for a voucher at the class, and we will send you one via email or mail within a few business days after the workshop. **"Do I have to be a resident of that community to attend that workshop?"** Nope! Our workshops are open to everyone (unless otherwise noted - which is extremely rare). You can attend a workshop that best suits your schedule even if it is in a different community than your own. **"Why is registration closed?** Can I just show up?" Yes, you can show up without registering! We close registration typically 1-2 days before the workshop to give the vouchers and materials to the presenters. However, you are always welcome to just show up and fill out a short form to request a voucher at the workshop. If eligible, we will send one to you within 1-2 business days after the workshop. **Voucher note**: Classes are free for everyone but vouchers are for residents of Franklin county or participating community (list here: https://www.communitybackyards.org/participate) 2026 Participating Vendors: City Folk's Farm Shop, Fisher's Gardens, Leaves for Wildlife, Scioto Gardens, Hoover Gardens & Gift Center, and the FSWCD/SWACO Compost Bin Sale. *when redeeming your voucher at a vendor, Please bring a physical copy of your voucher to receive an immediate discount on your purchase. Additionally, to keep up with number of vouchers that are given out, we have changed the expiration date on the vouchers to 30 days

Come out to Improving for our monthly iOS and Mac meetings. This Month's Presentation: Nothing yet. (You should volunteer). What is Cocoaheads (http://cocoaheads.org/)? CocoaHeads is a group devoted to discussion of Apple Computer's Cocoa Framework for programming on MacOS X and iOS (including the iPhone, iPad and Apple Watch). During monthly meetings, members present on their projects and offer tutorials on various programming topics. What is BuckeyeCocoa (http://buckeyecocoa.org/)? BuckeyeCocoa is a group of Objective-C/Swift developers/enthusiasts. We host monthly Cocoaheads and near-weekly NSCoder meetings in Columbus, Ohio. The meetings are free to attend. Presentations! Presenters welcome! We are always in need of people willing to present material. Any Swift and/or Objective-C related topic is welcome. Times can be 5 minutes (i.e. lightning talks) to a maximum of 2 hours. Interested? Contact info is on the BuckeyeCocoa website. To volunteer for a presentation contact us at @BuckeyeCocoa on Twitter. Follow us on Twitter! @BuckeyeCocoa (https://twitter.com/#!/Buckeyecocoa/) For more information: http://buckeyecocoa.org/

Thanks for being a part of the CABS Meetup Group! We meet @ the COFFEE UNDERGROUND on Indianola Avenue. We play many different games @ CABS - bring your own or play one of the OVER 2222 in our library. What are your favorite games? What was the last game you played? Hope to see and game with you soon! Check us out on Facebook! Doors open early on Saturday Mornings at 10am and around 4pm on Fridays if you are interested in learning new / simpler games ... or new to the hobby or just want to check us out come in early just after noon and we will show you around before the crowd grows. Stay for a game or two, an hour or two or for the day! Your first visit is free and after that it's $5 a meeting or you can join for the year! It's Your Move

**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** Like it or not, AI agents are now capable of turning a quickly written paragraph of requirements into a pull request that is ready to be integrated into real-world production applications and it's now our responsibility to make sure AI doesn't go rogue and take down prod - or corrupt our data by misunderstanding the requirements or our existing schemas. In this session we'll explore strategies to protect our codebases through unit and integration testing, documentation, and code review along with additional ways of providing context and guard rails to our AI agents as they carry out the work we've assigned them to do. By the time we're done, you'll have a firm grasp of the problem and understand some helpful options for protecting your codebase from vibe coding mishaps getting YOLOed into prod. **YouTube Link** TBD