Privacy

The controller is Astrum Holding, 60 rue François 1er, 75008 Paris, France. For any request about your data: contact@mathieukerbel.com.

What is collected, why, and for how long

• Email list (chapter 1 sample and blog posts): your email address and the page you signed up from, kept until you unsubscribe. Legal basis: your consent, given through double opt-in. Every email has an unsubscribe link.
• Book orders: email, amount, country and VAT details needed for the invoice, kept 10 years as French accounting law requires. Legal basis: the contract.
• Assistant conversations: the messages you send to the chat assistant and the tools it used, without your IP address, kept 30 days to improve the answers and detect abuse. They are stored with a random identifier that the chat keeps in your browser's local storage, so that the conversations of one browser can be grouped. Legal basis: legitimate interest.
• Bookings: the name, email and notes you enter in the cal.com calendar, kept for the duration of our exchanges. Legal basis: pre-contractual steps.
• Audience measurement: no cookie, nothing stored in your browser. Cloudflare Web Analytics counts page views, the sites visitors come from, their countries and how fast pages load. This site also counts, in its own database, the pages viewed (their address without what follows "?" or "#") and a few steps: chat opened, estimate shown, estimate downloaded (and its format), call booked, a click on a mission booking link, email sign-up, checkout started, purchase. Each count is stored with its date and time and a code computed from your IP address and your browser's user agent, which changes every day, so that the steps of one day can be followed; your IP address and user agent themselves are not stored. Kept 13 months, used only to measure this site's audience, not combined with other data. Legal basis: legitimate interest.
• Security: a salted, daily-rotated hash of your IP address to enforce rate limits, kept at most 30 days.

Processors

• Cloudflare, Inc. (hosting and audience measurement, United States)
• Anthropic, PBC (chat assistant, United States)
• Stripe Payments Europe, Ltd. (payment, Ireland)
• Loops (email list and transactional emails, United States)
• Cal.com, Inc. (booking, United States)

Transfers to the United States rely on the EU-US Data Privacy Framework or the European Commission's standard contractual clauses.

Your rights

You can access, correct, delete or export your data, object to its use, or withdraw your consent at any time, by writing to contact@mathieukerbel.com. You can also lodge a complaint with the CNIL (cnil.fr).

Cookies

This site sets no cookies of its own and uses no advertising or tracking cookie. The chat assistant keeps its random identifier in your browser's local storage (see Assistant conversations above); clearing this site's data in your browser removes it. The cal.com booking script loads only when you open a calendar on /architect or when a booking card is shown in the chat; cal.com may then set the cookies it needs to work (such as a Cloudflare security cookie).