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Licenses & acknowledgements

HushBook stands on a lot of open and public-domain work. Here's what we use, and the licenses it's offered under.

Last updated: 5 June 2026

The full text of every third-party license is bundled inside the app under Settings → Licenses. This page is a plain-language summary of the main credits.

Content sources

HushBook's built-in library surfaces public-domain audiobooks from:

HushBook is not affiliated with either project. Titles, metadata and availability belong to them and can change.

Typefaces

On this website

In the app

The SIL Open Font License is available at openfontlicense.org.

On-device speech recognition

Transcription runs entirely on your device via the HushBook Engine, which is built on whisper.cpp — a high-performance C/C++ implementation of OpenAI's Whisper automatic speech-recognition model, created by The ggml authors (originally Georgi Gerganov).

Full license texts for every component bundled in the app ship under Settings → Licenses.

This website

hushbook.app is a static site of hand-written HTML, CSS and JavaScript. Web fonts are served by Google Fonts. The waitlist form stores your email with Supabase — see our Privacy Policy for what that involves. No analytics or tracking scripts are used.

Spotted something we should credit? Email hello@hushbook.app.