Blog

"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.

January 26th, 2024 marks one year since all major browsers fully supported AVIF. For years, developers used `picture` elements to provide WebP or AVIF images while falling back to JPEG for browsers lacking support. Now, with universal AVIF compatibility, these workarounds may no longer be necessary.

Keeping up with web technologies can be overwhelming, especially for product owners who aren’t deeply technical or developers who want to avoid the complexity of polyfills. Baseline is an initiative that helps developers and businesses understand which web features are safe to use across all major browsers.

We're excited to announce the implementation of View Transitions API on our website, enhancing navigation fluidity and user feedback. This helps both us and you as a visitor to smoothly navigate our website from the very start of 2025. This UX update not only makes navigation more visually appealing, it also provides better feedback about page load states.

In 2024 we weren't only the sponsor but were also speaking at a sold out Performance.now() conference.

Core Web Vitals and SEO – it's a hotly debated topic that often leaves business owners and SEO professionals wondering where to focus their efforts. Some claim it's the key to ranking success, while others argue it's just another optimization rabbit hole. Let's cut through the noise and focus on what actually matters for your business in 2024 and beyond

The srsltid auto-tracking parameter already caused SEO havoc amongst site owners using Google Merchant Center. But issues aren't stopping there.

You'll find the slides of the "We Love INP & LoAF" talk at We Love Speed in Nantes.

Are your Core Web Vitals failing due to a LCP over 2.5s? Let's fix it! The Largest Contentful Paint (LCP) is one of the most important metrics in measuring web performance - more specifically - it's the one that measures loading speed. While absolutely vital for UX and conversions, still 40% of world wide sites fail at passing this metric. Let's deepdive in understanding and improving the LCP and get those numbers up!

In the pursuit of improving website performance, it's easy to fall prey to common misconceptions. Let's dive into some of these myths and uncover the truth behind optimizing your website's speed.

When it comes to building Single-Page Applications (SPAs), developers face unique challenges in meeting the Core Web Vitals requirements. CWV, while crucial for optimizing website performance, were not initially designed with SPAs in mind. Google has made efforts to accommodate SPAs, but as of now, there is no straightforward way for SPAs to excel in this aspect. In this blog, we will explore the impact of SPA architectures on Core Web Vitals and discuss potential solutions to overcome these challenges.

Round-Trip Time (RTT) is a crucial metric in web performance that measures the duration for a signal to travel from a client to a server and back, directly impacting Time to First Byte (TTFB) and overall loading times.

When debugging INP, it might be tempting to first look at elements that visitors interacted with. However, looking at this alone might be misleading and time-consuming.

We're still buzzing after yesterday's incredible events at Google I/O! It was a double Dutch delight for RUMvision, as both our upcoming integration with Google Baseline and our work on INP measurement were featured at Google's biggest event of the year.