eigendrum

a study of the vibrating plane

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privacy

Privacy and cookies

Eigendrum has no accounts, no sign-up and no login. It uses analytics but carries no advertising and no advertising cookies, so there is nothing here to consent to. This page says exactly what is collected, who receives it, and how to switch it off.

Last updated: 15 August 2026.

The short version

Who I am

Eigendrum is built and run by Basel Ashraf, an individual, not a company. For any privacy question or request, email u2679054@uel.ac.uk. I am the data controller for this site.

What is collected, and by whom

1. Hosting (Cloudflare)

The site is hosted by Cloudflare Pages, which processes standard server request data in order to serve pages at all: IP address, the URL requested, user agent, referrer and timestamp. This is ordinary web-server logging and is necessary for the site to function and to stay available.

The public visit total is an aggregate page-load counter stored in Cloudflare D1. Each production page load increments one number. No cookie, IP address, browser identifier or visit history is stored by this counter.

The deployed site also uses Google Analytics 4 and the separate presence service described below for aggregate measurements. The public counter does not attempt to identify unique visitors.

2. Analytics (Google Analytics 4)

Google Analytics 4 is used to understand how many people visit, which pages they read and roughly where in the world they are - country level. It sets cookies and Google receives your IP address as part of the request.

I have configured it not to record the URL fragment. That matters here specifically: the shape you draw or the formula you type is stored in the part of the address after the # - for example #f=p:1 + 0.3cos(5t). Browsers never send that fragment to the web server, and Analytics is set to report only the origin and path, so the shapes you make are not recorded in analytics.

Google signals, User-ID collection, user-provided data collection and ads personalisation are all switched off on this property.

3. Advertising

No advertising runs on this site. There is no ad network, no ad script, no ad iframe and no advertising cookie anywhere on Eigendrum. Two networks were trialled and both are now off: Monetag's In-Page Push, pulled after their own network served a fake-VPN scareware pop-up to a visitor, and Ezoic, whose consent management script rendered a broken, non-compliant cookie banner with hundreds of "legitimate interest" partners pre-selected and no working reject-all - reported publicly and removed as soon as it was found.

The space that would carry an ad instead carries a direct pitch: a plain mailto link inviting a real sponsor to contact me. It loads no script and no iframe, sets no cookie, and does nothing at all unless you choose to click it. Support toward the domain and hosting is voluntary, via a Ko-fi link in the footer.

If advertising ever returns, this section will say so plainly and name the network, and it must not repeat either failure above: no broken or non-compliant consent flow, and no format that can hijack a click, because drawing here is clicking and dragging.

4. Fonts and assets

The typeface is embedded directly in the stylesheet as a data URI rather than fetched from a font CDN, so no third party is contacted to render text. Every other asset the instrument needs is served from this domain.

What is stored on your device

You can clear or block cookies in your browser settings at any time. Blocking them does not stop the instrument working: the solver, the audio and the drawing are all local and do not depend on any cookie.

Legal bases (UK and EU GDPR)

Your rights

Depending on where you live, you may have the right to access the personal data held about you, to have it corrected or deleted, to object to or restrict its processing, to data portability, and to withdraw consent. If you are in California, you may have the right to know what is collected, to request deletion, and to opt out of "sharing" for cross-context behavioural advertising - I do not sell personal information.

To exercise any of these, email u2679054@uel.ac.uk. Be aware that I hold almost nothing directly: I see aggregate reports, not individual profiles. For data held by Google, their own tools are more effective than a request to me - My Activity and Ads Settings.

UK residents may complain to the Information Commissioner's Office; EEA residents to their national data protection authority.

Retention

Analytics data is retained according to the Google Analytics property setting, which is 14 months, after which it is deleted by Google. Cloudflare may retain ordinary server logs under its own schedule. The D1 visit counter stores only its aggregate total, not individual visit records.

Children

Eigendrum is a general-audience educational tool and is not directed at children under 13. I do not knowingly collect personal information from children. If you believe a child has provided personal information, email me and I will delete it.

International transfers

Google and Cloudflare may process data outside your country, including in the United States, under the transfer mechanisms set out in their own terms - typically Standard Contractual Clauses and the EU-US Data Privacy Framework.

Third-party privacy policies

Changes

If this policy changes materially, the date at the top of this page changes with it. The revision history is public, because the whole site is: github.com/BaselAshraf81/eigendrum.

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