Privacy Policy
Last updated: 2026-08-29
Medussa is a piano practice and study application for macOS, developed by Cristián R. Villagra.
Summary
Medussa collects no data. There is no analytics, no accounts, no advertising and no tracking. Nothing you do in Medussa leaves your computer.
This is not a promise — it is a technical property of the app. Medussa ships in the macOS sandbox with no network entitlement. Even if it wanted to send something, the operating system would not allow it.
What Medussa stores, and where
Everything stays on your Mac, inside the app's container or in folders you choose:
| What | Where |
|---|---|
| Your preferences (audio device, buffer size, language, appearance, visualizer settings) | The app's defaults, inside its container |
Your projects (.mdss) | Wherever you save them |
| Autosave copies | Next to your project, or in the container if the project has no file yet |
| Your chart library | The folder you chose |
| Instruments and audio samples you import | Wherever you keep them |
| Practice history | Inside your project |
None of this is transmitted. Medussa reads it only to show you your own work.
What Medussa accesses on your Mac
- Files you choose. Medussa can only open what you open, through a file panel or by dragging. It does not browse your disk.
- MIDI devices. So you can play. The notes you play are used to make sound, to drive the visualizer, and for your practice history inside the project.
- Audio output. For playback.
- Installed Audio Unit plugins. If you choose to use one, Medussa loads it from your system.
Medussa does not access the microphone, camera, contacts, location, calendar or photos, and does not request those permissions.
Third-party services
None. Medussa contains no analytics, advertising or crash-reporting SDKs.
It does include open-source libraries that run locally and do not access the network: FLAC, nlohmann/json, PicoSHA2, miniz, dr_wav, dr_flac and tiny-AES-c. Their full licences are in "About Medussa → Credits", inside the app.
Children
Medussa collects no data from anyone, of any age.
Your rights over your data
Since everything lives on your computer, you have full control: the files are yours, they sit in folders you chose, and deleting the app and its container removes what it stored. There is nothing to request from us and nothing for us to delete, because we hold nothing.
Changes to this policy
If a future version of Medussa adds a feature that uses the network, this policy will be updated before that version ships, and the change will be noted here with its date.
Contact
Cristián R. Villagra — cristianrvillagra@gmail.com