the WebKit team has rolled out a notable change in the 26.2 beta with support for two major performance APIs. This update moves Safari significantly closer to full Core Web Vitals support.
At Friday 17th of October, the 4th edition of SyliusCon took place. I travelled to Lyon to give a talk on Core Web Vitals debugging via DevTools.
Mozilla Firefox has just shipped support for Interaction to Next Paint (INP), one of Google’s Core Web Vitals metrics focused on responsiveness. This is great news for anyone monitoring site speed and user experience.
At Friday October 10th, the second edition of SEO Benelux took place. I travelled to Antwerp to talk about different sitespeed tools.
All roads lead to Rome, but it was our first time giving a talk in Italy. And it was a great succes! Want to find the slides, read about our Baseline integration, the Zitmaxx use case or how to improve webperformance for Hyvä, you find al the resources here.
At RUMvision, our focus is helping site owners make their sites faster. To do that well, we depend on the data browsers give us through APIs. Some of those APIs are already incredibly useful — but not all browsers support them consistently.
For years, site owners have been using Subresource Integrity (SRI) as a way to ensure that third-party scripts can’t be tampered with. However, keeping your script up to date is one of its challenges.
If you’ve been tracking real user performance, you probably already know: Chrome has long supported largest contentful paint (LCP), but Safari until now did not. That’s starting to change, and it’s a big deal if you rely on rumvision for insights.
Magento is a popular e-commerce system worldwide. At RUMvision, we'd like to share how Emico, one of our partners, ensured that their project, Zitmaxx.nl, became one of the fastest e-commerce websites we know of. And yes, this website was built using Magento.
Moin Kiel! I was happy to get everyone up to speed debugging and optimizing Core Web Vitals with RUM + DevTools. Looking for the slides? Here you go!
On July 18th I got to talk about about webperformance, while shipping and sipping at Mollie's biggest developer meetup yet! Here you find the slides.
Many agencies struggle with performance conversations because they rely on synthetic testing alone. Here's how Real User Monitoring changes the game and what we've learned communicating these insights to clients.
On June 10th 2025 I gave my talk "Why your pagespeed score is lying to you". In this you'll find the slidedeck, more info on how to improve the webperformance of your Magento shop and even info on a special we're running!
"Your site is slow" – four words no Hyvä developer wants to hear, yet only 51% of Hyvä shops achieve good Core Web Vitals scores. After years of optimizing Magento performance, we've identified the common issues preventing stores from reaching their full potential. In this guide, we'll explain not just what to fix, but why things fail in the first place. Your journey to better Core Web Vitals – and happier customers – starts here.
What happens to ecommerce when the lights go out? On April 28, 2025, a massive power outage hit Spain and Portugal just before noon. We combined electricity demand data with our own data, how others experienced it and the impact of an outage on ecommerce and non-ecommerce.
You want to ship native lazyloading or popovers to get rid of JavaScript and improve INP. And rather sooner than later. But there's a challenge: how to know if all of your users are ready for that feature?Baseline, a browser-wide initiative tracking 1000+ web features, is changing this. And with RUMvision's Baseline integration, you know exactly when your real visitors are ready for shipping modern features.
At RUMvision, we're always looking for smarter ways to optimize web performance data collection. That's why we're excited to announce we've begun rolling out support for a new browser API called fetchLater.
If you're still depending on unload events in your code, you need to act NOW. Chrome is starting to kill these handlers this month, potentially breaking your website's analytics and data-saving features. These events were never reliable on mobile, Safari already ignores them, and soon desktop Chrome will too. Here's why moving to better alternatives won't just save your code—it'll actually improve your site's performance.
Chrome is about to supercharge page navigation for millions of websites by ignoring a common performance-killing HTTP header. This under-the-radar change could dramatically improve your Core Web Vitals with zero developer effort by enabling bfcache for pages with Cache-Control: no-store. How do you know if you will benefit? (Spoiler: if you're using Magento, you probably won't.)
The back/forward cache (bfcache) is the most powerful performance optimization you've never heard of. While teams obsess over milliseconds of server time, they're missing out on entire seconds of improvement that's already built into every major browser.