Privacy Policy

Controller

Dirk Hofher
Schlesienstraße 2
74889 Sinsheim, Germany
E-mail: Info@cheetahlab.de

In short

This site sets no cookies, loads no JavaScript from third-party servers and uses no analytics services. There is no comment function and no visitor accounts. For the contact form, see its own section below. What is measured is an anonymous count of page views on my own server, from which individual people cannot be reconstructed.

Hosting

The site is hosted by ALL-INKL.COM – Neue Medien Münnich, Hauptstraße 68, 02742 Friedersdorf, Germany. The servers are located in Germany. A data processing agreement pursuant to Art. 28 GDPR is in place with the provider.

When the site is accessed, the host processes technically necessary data in what are known as server log files: the address requested, the time, the amount of data transferred, the status message, the browser identifier, the referring page and the IP address. The legal basis is Art. 6 (1) (f) GDPR — the legitimate interest in technically sound and secure operation. These log files are deleted by the host after seven days; I do not evaluate them.

The site's own counting

I would like to know which pages are read and whether an English version is worth the effort. For that, a count runs on my own server, without a cookie, without JavaScript and without any third party involved.

Per page view, the following are stored:

• the address requested — without the query string, so search terms are not stored
• the language of the page and the day
• the host name of the referring page, if present — without the path
• whether the request came from a machine (search engines are counted separately)
• a visitor identifier, formed as described below

The visitor identifier is a SHA-256 value derived from the IP address, the browser identifier and a random value that is re-rolled daily. The IP address cannot be recovered from it. It makes it possible to count the same person within one day as the same person — and no further than that.

Overnight, the individual rows are aggregated into daily figures and then deleted, together with the previous day's random value. After that, all that remains is the statement "page X was viewed this many times on day Y". An IP address is never stored at any point.

The legal basis is Art. 6 (1) (f) GDPR. Consent under § 25 TDDG is not required, because no information is stored on the end device and none is read from it.

Contact form

You can write to me through the form at Contact. It processes:

• the topic you picked,
• your name and e-mail address,
• the text of your message,
• the time you sent it,
• a hash of your IP address.

The IP address itself is not stored. The hash uses the same daily random value as the page count and serves one purpose only: limiting bulk submissions to at most three messages per hour from the same origin.

Your message is stored on this server and additionally sent to me by e-mail. Both happen at the same provider; no third-party service is involved. The double bookkeeping has a practical reason: if the e-mail is lost on the way, your message has still arrived.

I use what you send solely to deal with your enquiry. It is not passed on to third parties, not used for advertising and not fed into any analysis — not even into the page count described above.

The legal basis is Art. 6(1)(a) GDPR — the consent you give by submitting — and Art. 6(1)(f) GDPR, the legitimate interest in answering your enquiry.

Messages are deleted once the enquiry is settled. On request I delete them at once; an informal e-mail is enough.

The form sets no cookie either. It uses no captcha and loads nothing from third-party servers.

Cookies

No cookie is set for visitors to this site — not even one that would be "technically necessary". For read access the site deliberately does not start a session, and the contact form does without one as well.

Fonts

The fonts used (Archivo, IBM Plex Mono, Source Serif 4, all under the SIL Open Font License) are served from my own server. No connection to Google Fonts or any other third-party provider is made, and no IP address is transmitted there.

Links to external sites

Clicking the download link of a tool or the link to a 3D model takes you to a third-party provider. These are Docker Hub, GitHub, MakerWorld and Makeronline. In doing so, that provider learns your IP address, just as it would if you visited its site directly. I have no influence over its data processing; the privacy policy of the respective provider applies.

The intermediate step via this site serves solely to count the number of downloads. A counter is incremented by one — nothing more; who downloaded something is not recorded.

Weather data and LoRaWAN gateway

The published readings come from a private weather station in Sinsheim and contain no personal data. The same applies to the operating data of my own LoRaWAN gateway: only numbers are transmitted from there — how many devices were heard and how they are distributed across networks and spreading factors. Identifiers of third-party devices are neither transmitted nor stored. In both cases, transmission takes place over a closed interface with an access key and is neither reachable nor relevant for visitors.

RSS and search

The search runs entirely on my own server. Search terms are not stored — the counting records only the address without the query string. The RSS feeds contain the same content as the site and require nothing.

Your rights

You have the right of access (Art. 15 GDPR), to rectification (Art. 16), to erasure (Art. 17), to restriction of processing (Art. 18), to data portability (Art. 20) and to object (Art. 21), as well as the right to lodge a complaint with a supervisory authority (Art. 77).

The competent authority is the State Commissioner for Data Protection and Freedom of Information of Baden-Württemberg, Lautenschlagerstraße 20, 70173 Stuttgart, Germany.

In practice: for the page count there is nothing on file about an individual — neither IP addresses nor identifiers that could be attributed to a person. To that extent I cannot provide information either; that is not a shortcoming but a consequence of how the site is built (Art. 11 GDPR).

For messages from the contact form it is different: those contain your name and e-mail address. There your rights apply without restriction — an informal e-mail is enough and I will provide information or delete.

Changes

This policy describes the state as of 8 September 2026. If something about the site changes, this text changes with it.

Language

This English text is a translation provided for convenience. The German version is the authoritative one.