Privacy statement

Last updated: 23 October 2026

This statement explains what ludwig.fun does with personal data: what it keeps, why, for how long, who helps me process it, and what you can ask of me. I keep as little as possible and delete it as soon as it is no longer needed.

Who is responsible

ludwig.fun is run by Ludwig Fun, Keizersgracht 241, 1016 EA Amsterdam, the Netherlands. For anything about your data, write to privacy@ludwig.fun.

Reading the site

You can read everything on this site without telling me who you are.

• Language cookie. The site remembers the language you chose (English or Dutch) in one cookie, lang, which holds nothing else and is deleted when you close your browser.
• Page views. To show which notes are popular, the server counts views per note per day. It stores no IP address, cookie or other trace of you.
• Protection against abuse. To limit how often forms and the assistant can be used, the site works with a value derived from your internet address. It never stores the address itself; the derived value changes every day and can no longer be linked to anyone after two days.

There are no advertising or tracking cookies and no analytics tools, so the site shows no cookie banner.

The assistant

The assistant answers questions about my work. Your questions and its answers are sent to Anthropic, the company behind the Claude AI model that writes the answers (see "Who helps me" below).

• Without verifying, your conversation is not stored by the site: it stays in your browser tab and is gone when you close it.
• For each question the site records only that a question was asked, its cost and a non-identifying daily visitor code — never the question or the answer. These records are deleted after 12 months.

Verifying (for recruiters and clients)

To get detailed answers, share jobs with me or make a CV, you can verify with your work email address. I then keep:

• your name, company and work email address, the language you used, and when you agreed to this, verified and last visited;
• your conversation with the assistant;
• the jobs you shared and the CVs you made (see below).

The code you receive is stored only in scrambled form and is valid for a short time; a verification you don't finish is deleted after 24 hours. While you are verified, a cookie keeps you signed in; it is deleted when you close your browser and stops working after 24 hours. When you verify, I get an email saying who verified.

How long: everything about you is deleted automatically 12 months after your last visit. You can ask for deletion at any time with the "Delete my details" link in the assistant, or by email: it is then deleted at once, including any open session.

Legal basis: your consent, which you give when you verify. You can withdraw it at any time by asking for deletion.

Checking a job and making a CV

• Fit check. When you share a job (text, link or file), I keep the job text, the link or the file's name — never the file itself — and the result. A check you don't send to me is deleted after 30 days. A job you send to me is kept for 12 months, or until your details are deleted.
• Sending a job to me. I receive the job and the check by email.
• Tailored CV. A CV made for you shows your name and company ("Prepared for …"). It is kept for 12 months, or until your details are deleted, and I receive a copy by email.

The job text is sent to Anthropic to make the check and the CV.

Message Ludwig

When you send me a message, I keep the message, your name, the address you want a reply on and the language you wrote in, and I receive it by email. I use it only to reply to you. Messages are deleted 12 months after they arrive.

Legal basis: your request to be contacted (taking steps at your request).

Claude trainings

The page for my Claude trainings (in Dutch) has three forms and a payment route. This is what happens with your data in each.

The three forms — the waitlist for the basic trainings, a request for a team training, and signing up for the app training.

• What I keep. Your name and email address, and what the form you used asks for: the waitlist asks for your company and what you want to use Claude for; the team request for your organisation, the number of participants, when you would like it and what your team works on; the app sign-up for your app idea. I also keep which form it was, when it arrived, and a status I set myself (new, contacted, done). I receive each request by email as well.
• What you get. A short confirmation by email, sent when you send the form. It repeats nothing you typed.
• What I use it for. Only to answer you about the training you asked about: to tell you when new dates are known, to reply to a team request and to plan an app training. I do not add you to any other list; the notes by email are a separate sign-up.
• How long. Requests are deleted automatically 12 months after they arrive, or earlier if you ask me to.
• Legal basis. Your request to be contacted (taking steps at your request), and for the app sign-up also the consent you give by ticking the box.

Booking and paying a training day. You pay through Stripe, on Stripe's own payment page; the site never sees your card or bank details. Stripe asks for your name, email address, billing address and phone number, and — if you pay as a business — your company name and VAT number. Stripe sends you a receipt and an invoice, and keeps what it needs for the payment under its own terms. Resend sends you the booking confirmation by email (the date, what to bring and the questions to prepare your profile). I keep the booking and the invoice for seven years, as Dutch law requires me to keep my accounts.

Seats. The page shows how many seats are left per date. That number is a count of bookings, not of people; it contains no personal data.

New notes by email

If you subscribe, I keep your email address, the language you chose and when you signed up and confirmed. The subscription starts only after you click the link in the confirmation email; a sign-up that isn't confirmed within 7 days is deleted. Notes go out at most once a month. Every email has an unsubscribe link, and unsubscribing deletes your address straight away — no list of former subscribers is kept.

Legal basis: your consent.

Emails I receive

Messages, shared jobs, CVs, verification notices and training requests reach me as email in my own mailbox (Microsoft 365). I keep these as normal correspondence and delete them when they are no longer needed for our contact.

Who helps me

These services process data on my behalf, each under its own data processing terms, and may not use it for their own purposes:

• Railway — hosts the site, its database and its files, in the Netherlands.
• Anthropic (USA) — the Claude AI model behind the assistant, the fit check and the CVs. Anthropic does not use this data to train its models and keeps it only for a limited period under its terms.
• Resend (servers in Ireland) — sends the site's emails and the booking confirmations for the training days.
• Stripe — payments, receipts and invoices for the training days.
• Cloudflare Turnstile — the invisible check that tells people from bots on the forms.
• Microsoft — my mailbox.

Some of these are based in the United States. Where data leaves the European Economic Area, it does so under the European Commission's standard contractual clauses or the EU–US Data Privacy Framework.

The information about me in the assistant and in the CVs is my own; no data of yours is ever used to train an AI model.

Backups

Once a night, a copy of the site’s database is made, so the site can be restored after a fault. The copies are kept in the site’s own storage with Railway, which can only be reached through the site’s admin, and each copy is deleted after 30 days. Anything deleted from the site — at your request or because its time was up — is therefore also gone from the copies within 30 days.

Your rights

You can ask me to see the data I hold about you, correct it, delete it, receive it in a usable format, or stop or limit its use, and you can withdraw consent at any time. Write to privacy@ludwig.fun; I reply within four weeks.

If you think I handle your data wrongly, you can complain to the data protection authority in your country (in the Netherlands: the Autoriteit Persoonsgegevens).

Changes

When what the site does with personal data changes, this page changes with it, and the date at the top shows when.