duk. Terms of Use
Last updated 24 July 2026
These terms cover the duk. app itself. The website you are reading them on has its own terms of use.
1. Who publishes duk.
duk. is published by Betula Noir LLC, a limited liability company registered in the State of Texas, United States, based in Austin, Texas. In these terms, "we", "us", and "our" mean Betula Noir LLC.
- Publisher
- Betula Noir LLC
- Location
- Austin, Texas, United States
- Support
- support@betulanoir.com
2. Your licence
We grant you a personal, non-exclusive, non-transferable, revocable licence to install and use duk. on devices you own or control, for your own non-commercial enjoyment. You do not buy the software itself, you are licensed to use it.
3. What you may not do
You may not copy, redistribute, sell, rent, or sublicense duk.; reverse engineer, decompile, or disassemble it except where that right cannot lawfully be restricted; remove or alter any copyright or attribution; or use it in a way that breaks the law.
4. Beta software
duk. is currently distributed as a public beta through Apple's TestFlight and has not been released on the App Store. Beta software is unfinished by definition: it may contain bugs, behave unexpectedly, lose progress, or change substantially between builds, and a beta build stops working when it expires. Feedback is welcome and is the point of a beta.
5. Your progress and data
duk. collects nothing about you. It has no accounts, no analytics, no advertising, and no network calls. Your progress, statistics, and streaks are saved only on your own device using Apple's on-device storage, and are never transmitted to us or anyone else. We therefore cannot recover your progress if it is lost, and deleting the app erases it. The full detail is in the privacy policy.
6. Our content
duk., its name, its artwork including the duck and goose characters, its puzzles, and its code are owned by Betula Noir LLC and protected by copyright and trademark law. Screenshots and video of your own play are welcome, including in reviews, articles, and videos.
7. Distribution through Apple
duk. is distributed by Apple, and your use of TestFlight, the App Store, and your Apple Account is also governed by Apple's own terms. These terms are between you and Betula Noir LLC only. Apple is not a party to them and has no responsibility for duk. or for support of it; support comes from us at the address above.
8. Changes and availability
We may update duk., change its features, or stop distributing it. We may also update these terms; the current version is always posted here with the date it was last revised.
9. No warranty
duk. is provided "as is" and "as available", without warranties of any kind, express or implied, including any implied warranty of merchantability, fitness for a particular purpose, or non-infringement. We do not warrant that it will be uninterrupted or error-free. This is especially true while it is in beta.
10. Limitation of liability
To the fullest extent permitted by law, Betula Noir LLC is not liable for any indirect, incidental, special, consequential, or punitive damages, or for any loss of data or progress, arising from your use of or inability to use duk. Nothing here excludes liability that cannot lawfully be excluded.
11. Governing law
These terms are governed by the laws of the State of Texas, United States, without regard to its conflict of law rules. The state and federal courts located in Travis County, Texas have exclusive jurisdiction over any dispute arising from them.
12. Contact
Questions about these terms, or about duk. generally, go to support@betulanoir.com. See also the support page.