Marc Radziwill newsletter news from the web performance expert: exclusive tips and trends for web performance, JavaScript and workshops
Aktualisierung (Oktober 2025): Dieser Artikel wurde ursprünglich im Januar 2021 veröffentlicht. Die Unternehmensanalyse und Messdaten stammen aus Dezember 2020 und dienen als historische Referenz. Die grundlegenden Prinzipien für nachhaltige...
Update (October 2025): This post was originally published in October 2020. The RAIL model remains a valuable mental framework for understanding user-centric performance. While the industry has evolved to focus on Core Web Vitals (LCP, INP, CLS) as...
Update (October 2025): This post was originally published in October 2020. The lab vs. RUM distinction remains fundamental to performance monitoring. Since then, the ecosystem has matured significantly: the Chrome User Experience Report (CrUX)...
Update (October 2025): This post was originally published in September 2020. The adaptive loading pattern remains highly relevant for optimizing user experience across diverse devices and network conditions. Note that the Network Information API...
Update (October 2025): This post was originally published in September 2020. Third-party script management remains one of the most critical web performance challenges. The techniques described here (async/defer, CSP, SRI, conditional loading) are...
Update (October 2025): This post was originally published in September 2020 about the Deloitte "Milliseconds Make Millions" study. The study's business impact findings remain highly relevant and continue to be validated by subsequent...
Update (October 2025): This post was originally published in August 2020. Most techniques remain highly effective, though the ecosystem has evolved: native lazy loading is now widely supported (loading="lazy"), AVIF image format offers...
Update (October 2025): This post was originally published in July 2020. The optimization techniques presented here remain foundational and effective for improving Critical Rendering Path performance. While the tooling ecosystem has evolved (with...
Update (October 2025): This post was originally published in July 2020. In March 2024, Google replaced First Input Delay (FID) with Interaction to Next Paint (INP) as a Core Web Vital. This update reflects those changes with INP replacing FID...
Update (October 2025): This post was originally published in July 2020. The Critical Rendering Path concepts explained here remain foundational and evergreen. While modern performance measurement has evolved to include Core Web Vitals (LCP, INP,...
Update (October 2025): This post was originally written for Svelte 3 in 2020. Good news: The bind: directive syntax shown in this cheatsheet still works in Svelte 5! While Svelte 5 introduces runes ($state, $derived, $effect) for reactive state...
What are web vitals and why do we need them? Update (October 2025): This post was originally published in May 2020. In March 2024, Google replaced First Input Delay (FID) with Interaction to Next Paint (INP) as a Core Web Vital. This article has...
Intro to Svelte events Update (October 2025): This post was originally written for Svelte 3 in 2020. While DOM event handlers (on:click, etc.) still work identically in Svelte 5, component events have evolved significantly. Svelte 5 deprecates...
Update (October 2025): This post was originally published in January 2020 about Svelte 3. Since then, Svelte has evolved significantly with Svelte 5 (released in 2024) introducing runes, a new reactivity model, and improved performance. The core...
While working on a talk for an event in my local area, I thought about the main topics you want someone to know about web performance. My talk was about how to relate site speed and business metrics on a non-technical level. I came up with six...
Last year I published a blog post about why I moved my site from gatsby to Eleventy. I was struggling with Gatsby because of the enormous JavaScript overhead. If you are new to Eleventy, I recommend you read my first post before continuing. Now it's...
Lazy loading is a loading strategy that makes it possible to load something later. You may know this from Gatsby, React, or for images. Images or iframes below the fold can load later. Since version 76, Chrome supports native lazy-loading for images....
Intro to service workers So you probably landed here because you do not use service workers in your app and you want to know how they can help you. via GIPHY --> No need to worry. We go through all the service worker API in...
Intro to JavaScript performance optimization JavaScript performance optimization techniques for the JavaScirpt engine are simple to apply if you stick to some "rules" or better-said bits of advice. The implementation of these rules come...
The development of modern technologies continuously creates a multitude of new digitization possibilities. Digital change is simplifying many processes in business and society. All the advantages cover-up that digital technologies can also have...
2020 was crazy in many ways. It was an exciting year for my self-employment. I decided to take off from all my projects as of the first of January to reposition myself. I started blogging about web performance, accessibility, freelancing, and...
What should you measure to improve performance Web performance is a crucial indicator of the conversion rate. While you are optimizing your website's performance, you can work in different areas. For example, these areas could be the load time, the...
The Web Performance area is improving and has some awesome stuff to explore, but at the end of 2020, not all of our sites will be fast. Many tech people talk about 5G and HTTP/3, but there are much more new frameworks, tools and languages to explore....
If you find yourself caring about values like Bounce rate, Revenue, Time on site, page views, user satisfaction, online business success, you should care about web performance! Web Performance is not only a topic for nerds. Web Performance is about...
We help searchers by bundling and clearly presenting all online and delivery offers in the Allgäu. We support the small shops and service providers in the Allgäu, which we have become fond of and which we painfully miss in times like these. (Tante...