Which platforms does this barometer follow?

Sixteen: WordPress, Wix, Shopify, Squarespace, Webflow, PrestaShop, Joomla, Drupal, TYPO3, SPIP, Odoo, Ghost, Duda, Jimdo, GoDaddy and Framer. Each leaves a fingerprint in the page that no other product emits, which is what allows a site to be attributed without ambiguity. The rest of the parc is published together.

What exactly does this index measure?

The share of .fr sites built on each followed platform, read every week on a frozen panel of 15,000 domains drawn from Afnic's open data file. The shares are read on the domains that serve a page, and add up to a hundred.

How does it differ from global CMS rankings?

It covers the .fr parc, domain by domain, from a random draw in the registry of active domains. Global rankings cover the most visited sites on the planet, where the French web is a fraction and the platforms are spread differently.

What the .fr parc is built on

The platforms behind French websites, one by one, week after week.

The first reading is being published.

Method

The panel: The same panel as the other .fr indices: 15,000 domains drawn at random from Afnic's open data file, which lists the 4,590,553 active .fr domains. The draw orders every domain by the sha256 fingerprint of its name, and the published seed is enough to rebuild it.
The cadence: The home page of every domain is read each Monday, in the sweep that already opens the panel. The panel stays the same from one week to the next: a movement in the series is the parc deciding.
The reading: A platform is recognised by a fingerprint it alone leaves in the served page: an asset host of its own, a path layout of its own, or a generator tag it writes itself. Every site read falls in one case and one only, and the shares add up to a hundred.
The followed platforms: WordPress, Wix, Shopify, Squarespace, Webflow, PrestaShop, Joomla, Drupal, TYPO3, SPIP, Odoo, Ghost, Duda, Jimdo, GoDaddy and Framer. SPIP is on the list because the parc measured is the .fr parc. The rest of the parc is published together, under "outside the followed platforms".
The API: GET https://api.stileex.xyz/v1/series/fr/cms-share-wordpress/latest

Measured on the same panel, in the same weekly sweep: WordPress patch lag in France and Web encryption of the .fr parc