Digital Signal Processing

The next **Berlin C++ Meetup** hosted by think-cell takes place on **Tuesday, May 26**. Join us for an evening with the Berlin C++ community! This meetup is a chance to step away from your day to day work, meet other developers, exchange ideas, and have real conversations about modern C++ in a relaxed setting. \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\- ## **Talk** ### **Contract assertions on virtual functions** *Timur Doumler – Citadel Securities* Contracts assertions were introduced in C++26, but they cannot be applied to virtual functions. To close this gap, we first need to answer the question: how should contracts assertions behave in the presence of inheritance and runtime polymorphism? In this talk, Timur explores why this problem is harder than it looks. He reviews existing approaches from other languages, such as Eiffel, D, and Ada, highlights why they don’t fully translate to C++, and outlines the key design challenges involved. He then presents a concrete proposal for how contract assertions on virtual functions could work in C++, balancing correctness, safety, and usability. Along the way, the talk touches on good API design, the true meaning of the Liskov substitution principle, and how to reason about program correctness. \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\- 📅 **Date & Time:** Tuesday, May 26, 2026 – 18:30–21:30 📍 **Location:** Le Wagon Coding Bootcamp, Rudi-Dutschke-Straße 26, 10969 Berlin 🕒 **Agenda** 18:30 – Doors open 19:00 – Talk + Q&A 20:40 – Pizza, Drinks and Networking \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\- **RSVP now to save your seat!**

A \~2 hours watercolor - gouache painting lesson. **About this course** The total watercolor, gouache course consists of around 30 lessons that last 2 hours each. You can join at any time during the course. At the start of the event you choose which material you will use. The lessons will happen almost every Tuesday at 19:00-21:00 in Berlin. This course is aimed at introducing the painting process with watercolor, gouache as the main medium. These lessons cover the various techniques and methodologies. It is suitable for beginners and or even professionals who want to rationalize the painting process. It is being hosted by the visual artist [Miltos Despoudis](https://miltosdespoudis.gr/). **How much does it cost?** Check below: * 1 Tryout Lesson costs **5€.** You can do that only once. * 1 x Lesson (2 hours) costs **20€**. * 6 Lessons (2 hours each) cost **90€.** You can pay either by cash or card at the event. **How do I subscribe?** You need to reserve a spot here and come at the event. You can pay at the event. Please verify that you are attending so that we know and prepare accordingly with the art supplies. **What do I need?** Materials will be provided at the venue. You can also bring your own art supplies, it might be helpful to learn working with what you have. **More Info** This lesson is also known as "Watercolor Painting Lesson" or "Watercolor Workshop". Learn more about the lesson plan here: [https://creativesessions.art/workshops/watercolor-gouache-workshop/](https://creativesessions.art/workshops/watercolor-gouache-workshop/) **Refund Policy** On case by case scenario. If you paid for the tryout session we can refund up to one day before the event starts. If you paid for the lesson packet and used one of the tickets no refunds are possible.

Erlerne Meditations- und Entspannungsverfahren kennen und sorge damit für mehr Bewusstheit und Stressreduktion in deinem Alltag.

Yin & Essential Oil with Sound for Deep Relaxation is a calming and restorative experience designed to help you fully unwind and recharge. This class combines long-held Yin Yoga postures with soothing essential oils and healing sound elements to release tension from both the body and mind. Gentle stretches support deep relaxation while calming aromas and sound vibrations create a peaceful and grounding atmosphere. The slow pace of the practice encourages stillness, mindfulness, and nervous system regulation, allowing the body to soften deeply and the mind to settle. Perfect for stress relief, emotional balance, and complete relaxation. https://www.eversports.de/org/activity/c01d1b64-a798-45a0-8c8c-10240866f080

In diesem Kurs beschäftigen wir uns mit verschiedenen Texten aus unterschiedlichen Bereichen. Das können u.a. kurze Geschichten, Gedichte, Zeitungsartikel, Kolumnen oder Videos sein. Immer sind es Themen, die uns gefallen, die wir besonders interessant, wichtig oder manchmal auch richtig schlecht finden. Gemeinsam versuchen wir die Position der Autor*in, den Stil und die Argumentationsstruktur zu verstehen. Dazu diskutieren wir über das, was wir verstehen, welche Meinung wir zu dem Thema haben oder welche Fragen offen bleiben.
Gerne könnt ihr uns auch Themenvorschläge mitbringen oder zuschicken.
Der Kurs richtet sich an interessierte Menschen mit einem B2-Niveau (oder so ähnlich), die Lust haben sich weiter mit der deutschen Sprache zu beschäftigen und ihren Wortschatz zu erweitern.
Die Termine sind sporadisch.

Create the candle of your dreams in this premium scented candle workshop in Berlin, where creativity, sustainability, and craftsmanship come together. Hosted inside the Galleria Lucia Atelier, this immersive experience takes place in a historic artist building - a former factory now home to painters, designers, and makers. It's not a showroom or an office, but a real working candle atelier where so many candles come to life. During the workshop, you'll design a fully customized scented candle from start to finish. Choose your candle jar color, painted with sustainable, dishwasher-safe paints and designed to last up to 500 washes. Once your candle is finished, the glass can be reused as a drinking glass - making it both beautiful and responsible. Select from a curated range of premium fragrance oils, choose wax colors, finishes, and add natural crystals for a truly personal touch. You'll also create your own custom label, making each candle a one-of-a-kind piece. While you create, enjoy complimentary refreshments and learn expert tips on how to choose sustainable candles in the future and care for your candles so they burn cleaner and last longer. Surrounded by hundreds of candles and the authentic atmosphere of a Berlin candle atelier, this workshop offers a rare behind-the-scenes look into small-scale candle making - creative, intimate, and unforgettable. **Les Amis** is a women-only community of friendly souls. We provide access to hundreds of experiences that explore your passions and connect you with other event participants. **Check our website to learn more, and apply to join our community and events**: [lesamis.cc/apply](https://www.lesamis.cc/apply)

Cuban salsa classes every Tuesday. Join us, improve your skills, save lives and make friends! **Classes:** 19:00 - Improvers 2 (New routine starting every month) **Price: (Card payment only)** 1 class - 7€ 10 class pass - 49€ or 42€ reduced* (To use within 11 weeks. Valid for all our classes. It can only be used by one person per class. No refund possible) * Reduced price for students, Schüler, Azubis, H4-Empfänger, and pensioners/retired folks. A valid proof is needed. **Why should you learn Salsa, and why with us?** - It's great fun! - You get to know loads of new people. - No fix starting date - you can start any week. - No dress code - come in whatever you feel comfortable in. Note:No outside shoes in the room: socks or a pair of clean shoes will be required - No partner needed - we change regularly during the classes (bring all your friends though!) - You can help us make a difference! **What is Salsa4Water?** Simple! We teach Salsa and donate all our profits to the NGO Welthungerhilfe, which uses these funds for their local projects in Malawi. Welthungerhilfe fights for equal access to safe drinking water, sanitation, and hygiene in nearly 40 countries world wide. This gives you the chance to save lives while dancing!

Welcome to the PyData Berlin May meetup! We would like to welcome you all starting from 18:00. There will be food and drinks. The talks begin around 18.30 and the doors will close at 18:45. **Make sure to arrive on time!** Please provide your first and last name for the registration because this is required for the venue's entry policy. If you cannot attend, please cancel your spot so others are able to join as the space is limited. **Host**: **GetYourGuide** is excited to welcome you to this month's version of PyData. \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* The Lineup for the evening **Talk 1: Text2SQL in the Wild — Agentic Workflows & Semantic Models on Customer Data** **Abstract**: Translating a business user's natural language question into a reliable SQL query has huge value for business analysts, but doing it accurately at scale, on messy enterprise data, for complex queries, is incredibly difficult. This talk walks through a production Text2SQL system built on four pillars: semantic models built on customer data, RAG-based semantic search, an agentic verification and correction loop for building the SQL, and an evaluation framework for the entire process. Raw schema information is not enough for text2sql to work. Rather, thorough documentation including business metrics, synonyms, and qualified example queries, are required. We'll cover how to automate this documentation pipeline by mining query logs, generating descriptions with LLMs, and organizing everything into a knowledge graph and vector search index. From there, we'll dive into the agentic flow that takes a user question and iteratively generates, validates, and fixes SQL against a live database. The agentic framework analyses syntax errors and execution results to help it fix the SQL. Participants will leave with practical takeaways on RAG architecture for structured data, agentic retry patterns, and how to think about evaluation for Text2SQL systems in production. **Speaker**: Oren Matar **Bio**: Oren Matar is a principal data scientist and algorithms developer, with a background in social sciences and Bayesian methods. He specializes in NLP and time series forecasting, as well as agentic methods for data retrieval and processing. **Talk 2: Interpreting and Communicating Statistical Models** **Abstract**: Extracting actionable insights from complex statistical models remains a challenge, as raw coefficients are often uninterpretable due to nonlinearity, interactions, or hierarchical structures. This talk introduces a unified framework for model interpretation based on the principles of the Marginal Effects project ([https://marginaleffects.com/](https://marginaleffects.com/)). We move away from internal model parameters toward quantities of interest, such as marginal effects and adjusted predictions that translate statistical output into the "natural language" of the data. We will demonstrate these concepts in Python using the Bambi interpret module, showcasing a seamless workflow for interpreting Bayesian models built on PyMC. The audience will learn how to use the four primary interpretative pillars: Predictions, Comparisons, Slopes, and Marginal Means to compute average marginal effects and visualize conditional relationships. By the end of this session, you will be equipped to turn sophisticated GLMs and multi-level models into clear, rigorous narratives that are easily communicated to stakeholders. **Speaker**: Juan Orduz **Bio**: Juan is a Mathematician (Ph.D. Humboldt Universität zu Berlin) and Principal Data Scientist at PyMC Labs. He is interested in interdisciplinary applications of mathematical methods. In particular, time series analysis, Bayesian methods, and causal inference. **Lightning talks** There will be slots for 2-3 Lightning Talks (3-5 Minutes for each) between the two main talks. Kindly let us know if you would like to present something :) \*\*\* NumFOCUS **Code of Conduct** THE SHORT VERSION Be kind to others. Do not insult or put down others. Behave professionally. Remember that harassment and sexist, racist, or exclusionary jokes are not appropriate for NumFOCUS. All communication should be appropriate for a professional audience including people of many different backgrounds. Sexual language and imagery are not appropriate. NumFOCUS is dedicated to providing a harassment-free community for everyone, regardless of gender, sexual orientation, gender identity, and expression, disability, physical appearance, body size, race, or religion. We do not tolerate harassment of community members in any form. Thank you for helping make this a welcoming, friendly community for all. If you haven't yet, please read the detailed version here: https://numfocus.org/code-of-conduct \*\*\*

Come and celebrate and socialise with our community as we mark 4 years of biweekly social events and Demo Drops for the most vibrant community of producers in Berlin! 🎉❤️ Join us for another friendly Music Producers Meetup! This event is open to producers of all genres, skill levels, and backgrounds. Whether you’re a seasoned professional or just starting out, you’ll find a welcoming space to connect, share ideas, and get inspired. Bring your latest projects, network with like-minded creatives, and enjoy casual conversation over drinks and snacks. There’s no set agenda—just a relaxed atmosphere where everyone can mingle, exchange tips, and support each other’s musical journeys. Feel free to bring your music to share, and don’t hesitate to invite friends or collaborators. All genders, ages, and DAWs are welcome. Let’s keep building Berlin’s vibrant producer community together! We look forward to seeing you there! Stay connected: Telegram group: https://t.me/musicproducersberlin Instagram: @musicproducersberlin

There’s a peace and relaxation possible for everyone, that can occur with total ease, with a simple body process, called Access Bars ® Access Bar is like hitting the delete button on your computer’s hard drive. Negative thought patterns and mental chatter can be released and a space for peace, ease and new possibilities opens up. Best, everyone can learn this body process in a one day class. You can give the Bars® to your family and friends and to your clients. And of course you can let the Bars run also on yourself. Access Bars ® and Bodyprocess classes in English take place once a month, classes in German twice a month. Just ask for your desired date. Would this class be a contribution to your body, to your life, your business? Then I would like to have you in a one-day Access Bars. Consider this your invitation to a totally different paradigm for healing, change and transformation in all aspects of your life. The Access Bars class fee is 380 Euro, Practitioner License, Manual, Charts, food and drinks included. PLEASE NOTE THAT REGISTRATION IS ONLY POSSIBLE BY PHONE. For more information please visit my website: https://www.i-feel-so-good.de/home-en.html What happens in the brain during a Bars Session: https://www.youtube.com/watch?v=DgGbFRjqQPk If you have any question or you want to book a session, do not hesitate to contact me. Once a week we have an Access Bars ® evening that gives you the opportunity to exchange the Bars® and to meet other practitioners. ®

Join us for an evening on the practical side of AI agents. We'll dig into context engineering and why relevance matters more than prompt tricks, then look at what it takes to run autonomous agents safely alongside humans. Food and drinks provided — stick around after for networking. ✍️ RSVP asap as capacity is limited so grab your spot asap! 📅 **Date and Time** Wednesday, May 27, 2026 from 18:00-20:45 📍 **Location** [EBCONT office, beyond Quartier Heidestrasse, 34, 10557 Berlin](https://maps.app.goo.gl/aQGPgteqhQ2yrmx96) 📝 **Agenda** 18:00 – Doors open, arrivals and check-in 18:20 – Welcome note by EBCONT 18:30 – **Agent Builder Hope is not a strategy — relevant context for data driven agents** by Anderson Queiroz — Elastic *What are agents and context engineering? And why we think the "center of gravity" for context engineering is much more about relevance and your data than only prompts and memory management.* 19:00 – Q&A & quick break 19:15 – **Adapting to AI in Security** by Jenny Pinheiro — Tines *Best practices for autonomous AI and human interaction in the context of workflows.* 19:45 – Pizza, drinks & networking \*\*\* Invite your friends and join us for an evening of learning and networking with fellow engineers and speakers! Thank you to **EBCONT** for hosting and to **Tines** for teaming up with us on this one!

**Join Pitch & Feedback, a focused session designed for builders who want real, actionable input on their ideas.** This event brings together founders, freelancers, and curious minds in a structured format where selected participants present their ideas and receive direct feedback from the group. Whether you're refining an MVP (Minimum valuable product or service), validating a concept, or preparing to launch, this is a space to test your thinking with others who are building as well. How it works: * 6–8 selected presenters * Each gets 5 minutes to pitch + 10 minutes of structured feedback * Audience members contribute insights, questions, and suggestions Who should attend: * Presenters: founders, freelancers, or anyone working on an idea who wants honest feedback * Viewers: people interested in startups, product thinking, or networking with builders What you get: * Direct, constructive feedback on ideas * Exposure to different projects and perspectives * Opportunities to connect with potential co-founders, collaborators, or early supporters We will film the pitches and share the recordings with presenters (optional, only if they agree). This is not a passive meetup. It is a working session built around clarity, feedback, and meaningful connections. Session Details: * **📅 Thursday, 28.05.2026** * **🕕 18:00 – 20:00** * 📍 CI Space * Hosts: Erik & Belinda Limited spots for presenters. Register early if you want to pitch. This is how you save your spot: AS VIEWER: Just hit 'Join' here on Meetup and come along in person on the 28th : ) SIGN UP AS PRESENTER: 1\. hit the join button here on Meetup 2\. IMPORTANT: open the following FORM to hand in your pitch\. This helps us to get everything planned and you get a confirmation if your presenting spot is confirmed. Click or copy this link: https://docs.google.com/forms/d/e/1FAIpQLSc_ymogzg8FaHIpUqcOHS9pRXLVVC9InPkdJ74jjHUQ_km8iw/viewform Any questions, please reach out. Looking forward to your pitches & participation! Belinda & Erik

**Build for Everyone — Accessibility for Mobile** Flutter Berlin is hosting a joint meetup with Kotlin User Group Berlin and CocoaHeads Berlin, focused on building accessible mobile apps. **Location:** Hedwig-Dohm-Haus, Berlin We’ll cover both strategy and hands-on implementation — from understanding platform differences (Android, iOS, cross-platform) to real-world accessibility pitfalls and live testing. With: **Important:** Registration is via Luma, not Meetup. Please register here: https://luma.com/xo7d3vb4

While we are approaching the middle of the year and KotlinConf is just over - we are thrilled that Trade Republic hosts us again! So mark the date! **Line-Up:** 👉 **Lists, Sequences, and Flows: Scaling Data Processing in Kotlin without Melting Your Memory.** *by Daniela Valero* In this talk, Daniela shares her journey of meeting a major backend deadline while managing a data pipeline's memory footprint. You’ll learn how to transition from eager List operations to lazy Kotlin Sequences and jOOQ Streams (using database fetchSize chunking) to keep memory usage flat. Finally, we’ll explore using Kotlin Coroutines and Flow to introduce safe concurrency so your data processes quickly without straining your database. 👉 **The show must go on** *by Blagoja "Baki" Stamatovski* **👉 TBD** **Speaker Bios:** 🗣 **TDB**

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/

We meet to learn and practice American Sign Language and to grow our familiarity with Deaf culture. Facilitated by hearing folks (with a connection to a professional interpreter) using Deaf-created content. People of all ASL skill levels are welcome! As we learn, we hope to connect more with the Deaf community in Central Ohio. Join us as you're able! Come regularly or just once - whatever you're looking for! Each meetup will explore different topics related to ASL/Deaf culture, and will feature time to practice conversation with one another. Just bring yourself and a willingness to learn!

**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

**TBA**

Bring your work or your hobby, hang out, and code with us. Follow @buckeyecocoa for more information.

Some trained COUNT volunteers work together once a month at RMH (http://www.rmhc-centralohio.org/volunteer.php) as Housewarmers (usually on the 1st Sunday from 1 – 5 PM). Some schedule other shifts at their convenience. You may try this out with less fuss by following a "Fast track" or go through the normal process. Fast track • Arrange a time to shadow a COUNT volunteer. Call Dave Nohle at 614-268-9558 (cell). • Show up and try it out. • Complete application, etc. later. Normal process • Complete an online application (http://rmhc-centralohio.org/volunteer/). • Attend orientation in advance. • At orientation you will complete forms agreeing to keep family/patient info private and allowing a background check and tour the facility. • Complete one training shift. Daily shifts are: morning 9 AM - 1 PM, afternoon 1 - 5 PM and evening 5 - 9 PM. • Schedule shifts online using the on the RMH scheduling system (http://www.volgistics.com/ex/portal.dll/?FROM=32895). The Ronald McDonald House (RMH) provides housing and meals for families with sick children. The Columbus RMH is the largest in the world with 137 rooms. COUNT has been volunteering there since May 2014. Housewarmers work with RMH guests to provide a home-like environment - greet, assist with family needs, answer phones, give tours, assist with checkin/checkout, prepare guest rooms after checkout, clean facility, laundry, restock supplies and staff the front desk. RMH Housewarmers volunteer at least one four-hour shift a month. All Housewarmers must complete an application and agree to a background check before they can be full fledged volunteers.

Join us as we get together to see Paul Rudd in the latest comedy-drama-musical from John Carney, POWER BALLAD! The film follows a washed-up wedding singer, a fading boy band singer and a stolen hit song. Here’s a description, trailer and plan for this event: DESCRIPTION: Rick, a washed-up wedding singer, and Danny, a fading boy band star, bond over music and a late-night jam session. When Danny turns Rick's song into a hit, Rick sets out to reclaim the recognition he believes he deserves. Power Ballad is written/directed by John Carney, the master of the modern musical and creative mind behind Once, Begin Again and Sing Street! It stars Paul Rudd, Nick Jonas, Peter McDonald, Marcella Plunkett, Havana Rose Liu and Jack Reynor. BUZZ & ACCLAIM: The film premiered to rave reviews at this year’s Dublin International Film Festival where critics call it “a sure-fired crowd-pleaser” that “just might be the feel-good hit of the year!” Others say, “Paul Rudd delivers a career-best performance in this charmer” that’s both “hilarious and deeply moving!” SUMMER OF ICE CREAM, VOL 2: SHAKE NO. 8! Ranked the #1 Ice Cream Shop in Columbus in 2024, this is the perfect place to kick off our Summer of Ice Cream and grab a sweet treat after the show! Their menu features an array of traditional, specialty and vegan shakes, hot cocoa, and more! You can check out their full menu here: [https://www.shakeno8.com/menu.php](https://www.shakeno8.com/menu.php) PLAN: We’ll plan for a 7pm-ish showing and will meet in the lobby area about 20 minutes before the show. Once showtime is announced, advance ticket purchase is advised! Once you have yours, please list your seat number in the Comments section of this event. We'll head to nearby Shake No. 8 immediately following the show! Should be a fun one, Dan