Vocalis turns an EPUB into a chaptered M4B audiobook, narrated on your own machine — the web app runs in Docker, and the narration runs on your Mac's GPU. Nothing is sent to a cloud service.
Cloud text-to-speech means uploading your books and paying per word. Vocalis narrates on hardware you already own — and hands you a real audiobook, not a folder of MP3s.
Your books and the finished audio never touch a cloud TTS service. The server and the narrator talk to each other over your own network — that's the whole loop.
The output is a chaptered M4B — your book's actual chapters, ready for any audiobook player, not a pile of loose audio files.
The web app, API, and job queue run in Docker — a NAS is a good home. Narration runs natively on Apple Silicon's GPU through Metal, so a full-length book takes hours, not days.
The Setup page hands you a single line to paste into your Mac's terminal. It installs everything, registers a launch agent, and the narrator starts with the machine.
Upload a book, pick a voice, and come back to a finished audiobook.
A range of built-in voices ships with the server, ready on first start — and you can add your own.
Your book's chapter structure carries straight into the M4B, so scrubbing and bookmarks work like a store-bought audiobook.
Jobs run through a Postgres queue with progress, cancel, and a heartbeat that shows your narrator's hardware — even mid-book.
The narrator runs as a service and orphaned work is re-queued — a crash costs only the chapters in flight, never the book.
The first visit asks you to choose a password, and the server is locked to it from then on.
Add the web app to your phone or dock and manage the queue from anywhere in the house.
The server (web UI, API, Postgres) lives in Docker — on a NAS, if you like. The narrator is a native process on your Mac that fetches each book over HTTP, synthesizes on the GPU, and posts the finished audiobook back. It never touches the server's filesystem, so the two halves can be different machines with nothing shared between them.
The name says the rest: vocalis is Latin for "of the voice."
Docker for the server, and a Mac with Apple Silicon for the narrator.
Two commands — or paste the compose file straight into Portainer. Choose a password on first visit.
Open Setup and run the one-line command it shows you. That's the whole narrator install.
Pick an EPUB and a voice, and come back to a chaptered M4B.
Open http://<host>:8091, set your password, and the Setup page shows whether your narrator is connected and on what hardware.