Tim Kadlec helps organizations build faster, more effective websites through sustainable web performance practices. He writes about performance culture, metrics, and real-world optimization strategies.
237 articles from this blog
A reflection on how Google's speed ranking signal shifted performance focus from business impact to SEO metrics.
Exploring the origin and history of why hyperlinks are blue, from early browsers like Mosaic to modern web design.
An analysis of how modern fast hardware contrasts with sluggish software, urging developers to optimize resource usage.
Analysis of how major tech companies undermine mobile browser choice, harming user agency and the open web.
Analysis of native image lazy-loading's performance effects, showing overuse can harm Core Web Vitals.
Analysis of how fixing a minor checkout button issue at Olive Garden could boost revenue by millions, highlighting small UX changes at scale.
Analysis correlating Lighthouse scores with real-user CrUX data, revealing weak to negative correlations for Core Web Vitals.
![[Public] The cost of preload - Google Docs](https://allblogs.blob.core.windows.net/alldevblogs/thumbs/article-eddb9c51ddf5-full-39c5256f.webp)
Analysis of preload issues in web performance, discussing alternatives and concerns about Google Docs as a research medium.
Analysis of Ember.js performance data reveals Fandom mobile sites significantly increase median JavaScript processing times, skewing benchmarks.
Analyzes the performance and cost drawbacks of client-side A/B testing and explores edge computing as a superior alternative.
Using Netlify's redirect feature to proxy Cloudinary image requests through your own domain for performance benefits.
Explores the UX of skeleton screens for loading states, discussing their origins, benefits, and potential misuse in web development.
A developer analyzes a third-party widget causing severe performance issues, blocking the main thread for 2.5s on a high-end laptop and 48.6s on a low-end Android device.
Explores how the 'Age' HTTP header from CDNs like Netlify can interfere with link prefetching tools such as Instant.Page, impacting perceived performance gains.
A technical case study on A/B testing the instant.page prefetching library using Netlify's split testing and SpeedCurve for performance measurement.
Analyzes the performance cost of popular JavaScript frameworks like React, Vue, and Angular using HTTP Archive data.
Explains how to use WebPageTest custom metrics with request data to analyze script loading behavior in web performance testing.
A developer uses a new Shopify Liquid profiler to identify and fix a major performance bottleneck causing slow page rendering times.
The article argues for intentionally adding friction in development workflows to improve code quality and performance, using npm as a key example.
Explains how to use browser Feature Policies like oversized-images and unoptimized-images to catch and prevent common web performance issues.
