Answers about performance
Questions and answers from the Croct community about performance.
Personalizing the hero image, how do I keep LCP fast?
my hero image changes per audience, and the hero image is my LCP element on every landing page. i am worried that choosing it at request time means it swaps…
Coming off Optimizely on our headless storefront, does Croct avoid the render-blocking snippet?
our Hydrogen storefront has been running Optimizely and the snippet is a real cost. It loads synchronously on the critical path, and even with no experiment…
Keeping Oxygen's full-page cache while personalizing one hero section, is that possible?
Homepage on Hydrogen, served from Oxygen's full-page cache with CacheLong, hit rate is excellent and TTFB is around 40ms. Now the brief says personalize the…
Does resolving personalization server-side add a TTFB penalty?
evaluating croct and the one thing holding me back is TTFB. right now most of our pages are basically static, we sit around 180ms TTFB from origin and i do…
Will content resolution hold up during Black Friday traffic, and what if it times out?
Preparing a Hydrogen store for Black Friday. Last year a client-side testing script fell over under load and blanked our hero for a chunk of the morning. Not…
Does server-side fetchContent add a TTFB penalty on my Next app?
i moved our hero personalization out of a client hook and into a server fetchContent call in the App Router. my assumption was that the extra server-side…
What does personalization cost us in LCP on mobile?
80% of our traffic is mid-range Android. Current Lighthouse mobile: LCP 2.4s, TBT 190ms. With our previous client-side tool the anti-flicker snippet held the…
Croct fetch in my loader adds latency when the network is slow, how do I cap it?
Benchmarking my loaders. On a good connection the content fetch is fine. On a bad upstream connection it waits, and TTFB spikes with it. I do not want a slow…
Will adding personalization tank our Core Web Vitals scores?
We guard a 95+ Lighthouse performance score on our marketing site and I am protective of it. I have read the SpeedCurve criticism of anti-flicker snippets,…
Nuxt + Storyblok variants swap in after hydration, did I wire this wrong?
I have a Nuxt 3 app rendering Storyblok blocks, with Croct added as a client-side plugin: Expected: personalized block is rendered directly. Actual: the…
Worth adding preconnect hints for cdn.croct.io and api.croct.io?
Doing a resource-hints pass on a client site. Lighthouse flags third-party origins without preconnect. Which hosts does the Croct SDK actually talk to, and…
How much main-thread time does Croct event tracking add per page?
I am profiling INP regressions caused by third-party tags. Our current trace shows long tasks attributed to two analytics vendors, and I want to know where…