JustDummiesJust dummies — but seriously powerful ones.
It doesn't need to know who you are to work. There's no account to create, and nothing we measure is ever sold. Most of what follows runs without any cookie at all and cannot tell one reader from another; the one thing that can asks you first, and does nothing until you answer.
We use Cloudflare Web Analytics to know how many people visit the site and whether pages load quickly. This tool sets no cookie and doesn't identify anyone individually — it counts visits and load times, not people. Two further things are measured, deliberately. When you copy an install command, the site records which part of the page you copied it from, which command it was, the page's language, that part's position in the page, and when it happened. When you click the floating download button, it records which section of the site you were reading, the page's language, and when it happened. That is the whole of both records — no identifier, no address, nothing you typed, nothing that can be traced back to you. They answer one question, which is which parts of this site actually help. The playground records one thing of its own, described further down. None of this ever asks your permission, because none of it is capable of recognising you.
To understand how this page is actually read — which moment convinces someone, where people stop — the site can use Google Analytics. It is off until you accept it, and if you never do, nothing about you reaches Google. If you accept, it stores a cookie holding a random identifier, so that two visits from the same browser count as one reader rather than two, and Google becomes a second processor alongside Cloudflare, with the transfers outside the European Union that this implies. What it records is how you move through the page: the scenes you reach, the install command you copy, the download button you press, the tool you compare us against — and, on the API pages, the words you type into the search box, because what readers look for and fail to find is the most useful thing this site can learn. It is configured never to feed advertising, and what it collects about you is erased fourteen months after your last visit. Your answer covers this whole site, the playground included: whichever page you answer on, you are asked once and every other page follows that answer. In the playground it records one thing more, a press of Generate — never what you typed into the expression. You can change your mind at any time, here:
The playground runs the library entirely inside your browser, and nothing you type there is ever sent to a server — not a value you set on a constraint, and not text you paste into one. One thing is recorded when you press Generate: the shape of the expression you built, with the values left out. Where you wrote `StartingWith("ORD-")` what is recorded is `StartingWith(?)` — a question mark, never what was in its place — along with the page's language and when it happened. It answers which parts of the library people come here to try. Like the two above, it sets no cookie and cannot tell one reader from another. The playground asks the Google Analytics question below like every other page, and if you accept it there, it also records that a Generate happened — the press alone, with none of the expression.
The site is hosted on Cloudflare, which necessarily receives every request in order to serve it — your IP address and the pages requested, for instance. That's an unavoidable part of any web hosting, not a measurement we add; Cloudflare is our subprocessor for hosting and for the audience measurement above.
It's published by REEFACT, a single-member SARL registered under SIREN number 804 026 482, headquartered at 134 rue de Chevilly, 94240 L'Haÿ-les-Roses, France, represented by its manager Sylvain Aurat.
If you have never accepted Google Analytics, this site holds nothing that identifies you individually, and there is in practice nothing to correct or delete about you. If you have accepted it, refusing above stops the collection from that moment; to have what was already collected erased, or for any other question, write to privacy@reefact.net.
Last updated: August 23, 2026.