Core Web Vitals for Content Sites, Decided Before Launch
Most Core Web Vitals advice is about fixing what broke. These are the decisions that are cheap now and expensive later — especially the one about reserved ad space.
Sep 23, 2026Performance
Core Web Vitals, caching strategy and cost per thousand visits — what the published numbers mean once a page is actually served from an edge network, as this site is.
How to Fix CLS Caused by Ads, Before the Ads Arrive
Ads are one of the biggest sources of layout shift on the web, and the fix has to be built into the template before your first ad loads. Here is how CLS is actually calculated, the four techniques that actually hold a slot, and the trade-off nobody publishes a number for.
Sep 23, 2026INP: What Actually Moves It, and Why Your Handler Is Only One Third of the Story
INP is not a measure of how fast your event handler runs. It has three documented phases, two of which happen outside your code — before your handler starts and after it finishes. Here is the mechanism, and the part of it that main-thread work you never associated with clicks quietly inflates.
Sep 23, 2026LCP: Finding the Element That Decides Your Score
The largest contentful paint is not a fixed property of your page — the candidate can change while the page loads, and an element that gets removed can still be the one that counts. Here are the four documented sub-parts, the element types that qualify, and why the algorithm stops when you scroll.
Sep 23, 2026How to Measure TTFB Without Fooling Yourself
"TTFB is 800 ms" is a number with no meaning until you say where it starts and where it was measured. Here is how to split TTFB into its four components with curl, what the components looked like on a real static site, and why a single measurement is close to worthless.
Sep 23, 2026Responsive Images: srcset and sizes Without Guessing
sizes describes the slot you are rendering into, not the size of the file — and if you omit it, the browser assumes 100vw for every candidate. Here is how the selection actually works, why lazy-loading the wrong image costs more than it saves, and what the specification does not promise.
Sep 23, 2026