Magnitide opens your calibre library as it is, read-only, so calibre keeps working alongside it. Underneath is a native Rust core and a Tauri desktop app, built to stay quick with 50,000 books and more.
GPL-3.0 · In active development: see the roadmap for what's done and what's next.
Everything a library manager should, on your own files, in your own folders.
Open your calibre library as it is, read-only. Magnitide never writes to it, so calibre keeps working. When you're ready to edit, import it into a Magnitide library of its own: books become copy-on-write clones where the disk allows it (no extra space on APFS, Btrfs or XFS), and your custom columns come too.
Covers, or a sortable, resizable, reorderable table. Search with author:, tag:,series: and your own fields (#pages:300), quotes and - to exclude. Shelves of your own, and a details panel with everything about a book.
Author sort names, omnibus editions, several series per book, custom fields of eight kinds. Find Metadata looks books up on Open Library and Google Books and lets you take what you want, field by field. Folders and file names follow your edits, and metadata can be written back into EPUB files.
Kobo, Kindle and other devices show up when plugged in. Books go over in the format each reads best, converted from EPUB to KEPUB or AZW3 natively (calibre is only a fallback), and shelves become collections on a Kobo, for Kobo's own app and KOReader alike.
An optional library server with an OPDS catalogue for reading apps, a simple page for e-reader browsers (Kobo's gets KEPUBs made on the fly), and KOReader progress sync. Off by default, read-only, with an optional password and a QR code to scan.
Nine themes (light, dark, sepia, the four Catppuccin flavours, Dracula and Alucard), any of their accents, an interface size from 80% to 200%, and add-on theme files that are checked colour data, not CSS. This page wears them too: try the theme menu at the top.
Magnitide has a plugin API of its own, and runs the calibre plugins you already rely on.
Small, sandboxed WebAssembly components in .mgp files, added in Settings → Plugins. A plugin can do only what its package declares, gets a fresh instance per call, and a crash is a plugin error, not an app crash.
Written in any language with a WebAssembly toolchain. A Rust SDK, a template and two example sources (Open Library, Goodreads) are in the repository.
The API and SDK →Metadata sources join Find Metadata. Toolbar plugins work on the selected books from the Plugins button or the book menu; their windows open as in calibre, and what they change comes back into the library through Magnitide's own editing. File-type plugins run when books are added, and readers and writers handle their formats.
They run in whichever host you choose:
Conversion, catalog, device, store, viewer and editor plugins aren't supported.
Hosts, coverage and limits →
metadata.db and the book folders and changes nothing. Its tests check the file is
unchanged byte for byte.
Builds are published on GitHub Releases. Magnitide is in active development, so expect rough edges and frequent updates.
Arch Linux: the magnitide-bin package is on its way to the AUR. Until then, build it from the repository (it repackages the release's .deb):
git clone https://github.com/obscuredetour/magnitide.git
cd magnitide/packaging/aur/magnitide-bin && makepkg -siwasm32-wasip2 target, Node with pnpm, and the Tauri CLI:rustup target add wasm32-wasip2
cargo install tauri-cli --version "^2" --locked
pnpm --dir crates/app/ui installcd crates/app
cargo tauri dev
cargo tauri build --bundles appDetails in the README.