The blog post discusses the importance of setting expectations and measuring the impact of web performance optimizations. It emphasizes the need to clearly define which metrics will be impacted and how they will be measured, in or...
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Tim Kadlec is a web performance consultant helping organizations improve site speed and effectiveness.
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The author has launched perfwork.com, a job board for web performance enthusiasts. The site is aimed at connecting companies and individuals looking for roles that involve web performance work. The author shares the motivation beh...
The blog post discusses the problematic 'single visionary' narrative in product development, emphasizing the importance of humility, curiosity, and collective input. It highlights the need for principles, regular user conversation...
The blog post discusses the misconception of relying solely on web performance metrics to determine the effectiveness of a website. It emphasizes the importance of considering user experience and user goals in addition to performa...
The blog post discusses the changes Chrome made to how they define 'contentful' for Largest Contentful Paint and First Contentful Paint. It highlights the differences in the logic applied to both and provides examples to illustrat...
The blog post revisits the Golden Rule of Performance, which states that 80-90% of the end-user response time is spent on the frontend. The author analyzes data from 2006, 2012, and the present day to see if the rule still holds t...
The author is returning to web performance consulting after working on WebPageTest for 2.5 years. He is excited about the changes in the performance industry and looks forward to helping organizations improve their site speed and ...
The blog post discusses the potential benefits of Apple allowing other browser engines to be used on iOS, emphasizing the importance of browser diversity. The author highlights the potential for Safari to compete with other browse...
The author discusses the importance of investing time in reading RSS feeds and how it has been a valuable habit for personal and professional growth. He reflects on the changes in his reading habits and the impact of technology on...
The blog post discusses the issue of variability in web performance data and how it can reveal real issues with a website. The author emphasizes that variability is natural and should not be glossed over, as it can hide important ...
HTTP/3 work started in 2012 with Google working on QUIC, adopted by IETF in 2017, RFC’s published in June 2022. HTTP/3 brings faster connection setup, better header compression, stream prioritization, packet loss handling, tunable...
The blog post discusses the high amount of time spent processing JavaScript on the median mobile page where Ember.js was detected. The author found that the median site using Ember.js spent 21.9s dealing with JavaScript when loade...
The blog post discusses the true cost of client-side A/B testing, focusing on the impact it has on site performance and business revenue. It explains how client-side A/B testing scripts can significantly slow down page load times ...
The author discusses the benefits of using Cloudinary to optimize images and the process of proxying requests to Cloudinary through Netlify to avoid a separate domain connection. The author also shares the results of using Cloudin...
The blog post discusses the concept of skeleton screens, which are used to display the outline of content while it is loading. It explores the effectiveness of skeleton screens, the conditions under which they are beneficial, and ...
The blog post discusses the impact of a third-party widget on website performance, highlighting the significant difference in performance on high-end and low-end devices. It emphasizes the importance of considering the impact on u...
The blog post discusses the impact of the Age header on prefetching and how it affects the performance of web pages. It explains how the Age header is used by upstream caching layers and how it interacts with the browser's caching...
The author wanted to test instant.page on his site and ran a split test to compare the performance of the site with and without instant.page. He used Netlify and SpeedCurve to set up the split test and track the performance data. ...
The blog post discusses the performance cost of using JavaScript frameworks such as React, Vue.js, Angular, and jQuery. It analyzes the impact of these frameworks on the network, parsing, execution, and memory, and compares the am...
The blog post discusses the use of snippets in developer tools to quickly execute code in the console. It also explains how to use WebPageTest custom metrics with request data to distinguish between scripts included in the initial...