Fathom

Fathom is a reading interface for books, manga, comics and PDFs that already live in Jellyfin. It runs as one Docker container, reads your reading libraries over the Jellyfin API, and presents them cover-first rather than as rows of filenames.

Early

Browsing works: a featured shelf, recent additions, library and collection browsing, and a title detail view with contributors and metadata.

There is no reading-progress tracking, no ratings or reviews, no personal collections and no recommendation engine. Fathom is a nicer way to look at a reading library, not yet a reader.

Requirements

• A running Jellyfin server with at least one book, comic or mixed library
• A Jellyfin API key and the user’s UUID (not their username)
• Node.js 24 LTS from source. Node 22.5 is the hard floor — Fathom uses the built-in node:sqlite module, which does not exist on Node 18 or 20.

Running it

docker run -d \
  --name fathom \
  -p 3000:3000 \
  -v ./fathom-data:/data \
  -e FATHOM_DATA_DIR=/data \
  -e JELLYFIN_URL=http://your-server:8096 \
  -e JELLYFIN_API_KEY=your-api-key \
  -e JELLYFIN_USER_ID=your-user-uuid \
  getcoral/fathom:latest

Fathom serves on port 3000 and exposes /healthz.

Every JELLYFIN_* variable is optional. With none set, Fathom sends you to /setup on first run and stores the connection in its own SQLite database. The environment variables exist so an operator who configures everything through compose never has to open the UI; /setup still lets you override them locally.

Environment

Verified against fathom/.env.example and fathom/src.

Variable	Required	Default	Purpose
JELLYFIN_URL	No	—	Jellyfin base URL. Must resolve from inside the container
JELLYFIN_API_KEY	No	—	API key from Dashboard → API Keys
JELLYFIN_USER_ID	No	—	The user’s UUID, not their username
JELLYFIN_USERNAME	No	—	Optional. Opens a real playback session
JELLYFIN_PASSWORD	No	—	Optional, paired with JELLYFIN_USERNAME
FATHOM_DATA_DIR	No	./data	Where fathom.sqlite lives
HOST	No	0.0.0.0	Interface the server binds to
PORT	No	3000	Port the server listens on

Storage

Fathom keeps its Jellyfin connection and local overrides in a SQLite database at ./data/fathom.sqlite, or under FATHOM_DATA_DIR if you set it. In the published image that is /data — mount it, or you will redo setup on every container replacement.

Library layout

Fathom reads whatever Jellyfin already exposes as a book or mixed-content library. It does not scan the filesystem itself and does not write to your media, so how you organise files on disk is entirely Jellyfin’s business.

From source

git clone https://github.com/Get-Coral/fathom.git
cd fathom
pnpm install
cp .env.example .env
pnpm dev

Script	Purpose
pnpm dev	Dev server on :3000
pnpm build	Production build
pnpm start	Run the production server (node server.mjs)
pnpm typecheck	TypeScript check
pnpm check	Biome lint + format check
pnpm test	Vitest

pnpm start is the production entrypoint and is what the Docker image runs. pnpm preview serves the Vite build and is for local inspection only.

Related

• Fathom vs Kavita and Komga — whether your books belong in Jellyfin at all
• Aurora — the same idea for video
• Jellyfin API Client — the typed client Fathom is built on
• Get-Coral/fathom on GitHub