A fast first image helps little if filters freeze or checkout shifts as images load. A local lab says little about real mobile traffic.
Store performance: loading, response and stability
Measure whether pages become visible, respond to shoppers and keep elements stable. Evaluate speed on real devices and shopping tasks.
Research context: web.dev · Core Web Vitals ↗
Use development tests to find regressions and field data to evaluate experience. Separate mobile and desktop. Measure LCP, INP and CLS alongside task failures.
Try the pattern
Task and expected result
- 01
Open Famme on a narrow screen: reserve space for banner and product images before they load.
- 02
Try multiple filters and basket actions. Observe delays and errors; do not conclude from an aggregate Lighthouse score alone.
- 03
Navigate learning without JavaScript: server-rendered text and category links should remain accessible.
- 04
Record mobile/desktop, network, URL and action when you find slowness or layout shifts so the issue can be reproduced.
How to investigate value
Define audience, exposure, denominator and primary outcome before starting. Record what could invalidate the data.
Watch for side effects
Data loss, incorrect variant allocation, returns/refunds, margin, accessibility and mobile performance.
This is a proposed investigation, not a measured result. Choose one hypothesis and define the audience before testing.
Build a measurement plan for this concept ↗