This year’s edition of WCEU 2025 took place in beautiful Basel, Switzerland. Over 1,860 participants from 84 countries joined the event, and 70 speakers took the stage to share their insights on WordPress development, optimization, design, security, and everything in between. Participants began with Contributor Day, working together on core, documentation, translations, and support to improve various aspects of WordPress. Next were practical workshops on topics such as block development and automated testing which offered opportunities to hone skills and tackle real-world challenges.

Our recap from WCEU2025

As Osom Studio, we stay close to everything that’s happening in the WordPress world, so attending the biggest WordPress event of the year was a natural choice. For us, WordCamp Europe is more than just talks – it’s a chance to meet the community in person and be inspired by the people who shape the ecosystem.

We’re sharing a few highlights below – the sessions that stood out most to us. If you couldn’t make it to Basel, these are definitely worth catching up on.

Client-side Web AI Agents – Jason Mayes

Jason Mayes, Google’s Web ML lead, specializes in bridging machine learning and web browsers. In his presentation, he demonstrated how to run local LLM models directly within websites, keeping all processing on the user’s device.

While it might seem redundant given existing LLM APIs and tools like ChatGPT, Mayes highlighted a key advantage: complete data privacy, as information never leaves the user’s machine.

Current applications remain limited, but the concept of tightly integrating local LLMs with website context opens intriguing possibilities. The main barrier today is the substantial 1.5GB model size for Gemma 2, though Mayes revealed that Google is exploring pre-provisioning Chrome with local LLMs to reduce bandwidth requirements.

The full presentation is worth watching and available on WordPress.tv.

From Reactive to Proactive: Modern Observability – Mathieu Lamiot 

Mathieu Lamiot is VP Engineering  of WordPress at group.one. His talk focused on how a proactive mindset –  instead of a reactive one – helps teams detect, understand, and resolve issues before they affect end users. He shared techniques for tracking not only bugs, but also key business signals, and showed how to build alert systems based on event logic rather than failure.

Observability, as Mathieu presented it, is much more than tools like Sentry and crash logs. It includes tracking drops in sales, spikes in signups (possibly caused by bots), and other business anomalies. These insights let teams trigger alerts based on data and behavior – not just breakdowns. We found this approach especially relevant for mid-sized and larger teams looking to gain better visibility of business events, rather than pure crashes. You can observe the data in excess events (e.g. bots filtering failing allowing for massive usage), or lack of events (e.g. a silent error on a checkout page, wrong product configuration on ecommerce resulting in lack of sales). 

Complementing this proactive monitoring approach, automated visual regressions testing serves as another layer of observability. Tools like BackstopJS can detect unintended layout shifts, broken CSS, or UI regressions that traditional functional tests might miss. By capturing screenshots across different browsers and viewports, teams can automatically flag visual anomalies before they reach production, ensuring that business-critical elements like checkout flows or signup forms maintain their intended appearance and functionality. And when you think about broken UI on an ecommerce site, this may be a reason there is a drop in sales which would be reported by business events monitoring as an anomaly. All 3 layers are tightly coupled.

If you’re interested in monitoring that goes beyond “what broke?”, this talk is a must-watch. We see huge potential in this direction – proactive observability isn’t just a toolset, it’s a strategy: build, observe, react – before problems explode.

Cyber Resilience Act and WordPress – Oliver Sild

Oliver Sild is the co-founder and CEO of Patchstack, a company focused on securing the open-source ecosystem – with WordPress at its core. He’s been a vocal advocate for better regulation, clearer responsibilities, and smarter collaboration when it comes to security across the plugin and theme ecosystem. In his WCEU 2025 session, Oliver explained the implications of the upcoming EU Cyber Resilience Act (CRA) – a legislative framework that will significantly impact WordPress developers, site maintainers, and product vendors in the EU. His talk offered a much-needed breakdown of what to expect and how to prepare.

We had the pleasure of discussing this topic with Oliver on our podcast Osom to Know last year. In that conversation, we explored the challenges of online trust, new responsibilities for open-source maintainers, and why younger generations are especially exposed to certain types of threats. If you’re curious about how security, education, and real-world risk intersect, don’t miss this episode: 🎧 Why Gen Z Gets Scammed – Interview with Oliver Sild.

From Basel to Kraków: WCEU 2026 Announced!

To wrap things up, what makes this year’s WordCamp Europe even more exciting for us is the news that the next edition will take place in Kraków.  We can’t wait to welcome the WordPress community in Poland.

Hope to see you there!