As software engineers and technologists its common to have access to some powerful devices and super fast bandwidths. It’s highly likely that you will be developing/testing on a high end Mac (or similar) or pulling out an expensive mobile device such as an iPhone from your pocket. But we need to be careful that this […]
This article is noticeably light on numbers for a web performance article but hopefully relevant nonetheless. What mattered to me to write about was software acceptance and getting buy-in for web performance solutions. Essentially: did people accept the tool you proposed to work with? Did they feel a sense of ownership of the results of […]
A 300ms improvement may sound like a big win to someone immersed in web performance optimization, but for most people, mentioning milliseconds doesn’t usually resonate or seem meaningful. Whenever I’ve mentioned how we could save a few hundred milliseconds to an executive, my proposal was often met with quizzical looks and a nod to proceed, […]
The browser makes use of a single main thread for executing most important tasks, it’s responsible for running JavaScript, handling user interactions, and updating the DOM. The main thread also performs the layout and painting. These are browser’s high-level tasks that are bound to the main thread, so what is this “main thread” we’re talking […]
In most organizations, even before creating a website, teams select the technologies to use, often without having defined the functional scope and desired user experience. I won’t infer here on their motivations, but the fact is that they present this to stakeholders who often do not know what it is about, and validate from a […]
For years, traditional optimization techniques like caching and resource compression have been the go-to solutions for speeding up websites. They’ve been effective at reducing load times and easing server strain. Performance tools have made these advanced techniques more accessible to site owners, whether they have technical expertise or not. However, as user expectations for near-instant […]
2024 was the year my public speaking career really took off – I did a quick count and realized I’ve done 10 speaking events about web performance across 5 countries and 2 continents. You could even argue Great Britain is another continent after Brexit (3 continents then! 😉) Giving my talk “The state of Web […]
In the last few years, one of the biggest sources of excitement and anticipation in the React community has been a tool known as React Compiler (previously React Forget). And for a good reason. The central premise of the Compiler is that it will improve the overall performance of our React apps. And as a […]
Every line of code has a cost – but some lines cost more than others. This rather Orwellian-sounding statement might seem stark, but for web performance engineers, it’s a useful perspective when considering cloud costs. Why Should You Care About Costs? Cost reduction directly impacts the bottom line. Money saved can be reinvested into meaningful […]
If you’re reading this, you probably have spent time looking over performance traces, flame charts, network logs and waterfall charts. The key word here is looking. Paint timings like FCP and LCP, Interaction to Next Paint, Long Animation Frames – many of the metrics and APIs we use measure the visual experience of using the […]
Real world examples of how over-optimizing for metrics can be at odds with performance. “When a measure becomes a target, it ceases to be a good measure” An adage attributed to Charles Goodhart, a British economist. Overview In web performance, Goodhart’s law surfaces when optimizing for metrics and optimizing for UX might lead to opposite […]