Install on Linux

Five ways to install on Linux: AppImage, .deb, .rpm, Flatpak and tarball, plus the AUR package. What each one can do, how each updates, the Flatpak sandbox limits, the Steam Deck, the odm link handler, and where the data lives.

Desktop app

Which one

Build	Best for	Updates	Local AI and agents
AppImage	Any distribution, no root	Replaces itself from inside the app	Yes
.deb	Debian, Ubuntu, Mint, Pop	The app installs the next .deb itself, asking for your password	Yes
.rpm	Fedora, RHEL, openSUSE	The app installs the next .rpm itself, asking for your password	Yes
Flatpak bundle	Immutable desktops, Steam Deck desktop mode	The app installs the next bundle with your system's flatpak and restarts	No: the sandbox cannot start other programs
Tarball	Portable, custom locations	The app unpacks the next archive over itself, asking for a password if the folder needs it	Yes
AUR (`open-dungeon-master-client-bin`)	Arch and derivatives	Your AUR helper	Yes

AppImage

chmod +x open-dungeon-master-client-0.17.2-x86_64.AppImage
./open-dungeon-master-client-0.17.2-x86_64.AppImage

The AppImage carries a static runtime, so it runs on Fedora 41+ and Ubuntu 24.04+ without libfuse2. Keep it somewhere permanent: the in-app updater replaces the file in place.

.deb and .rpm

# Debian, Ubuntu
sudo apt install ./open-dungeon-master-client-0.17.2-amd64.deb

# Fedora, RHEL
sudo dnf install ./open-dungeon-master-client-0.17.2-x86_64.rpm

The package installs to /opt/open-dungeon-master (with a launcher in /usr/bin), a desktop entry, and the odm:// handler through the desktop file's MIME type.

Flatpak

flatpak install open-dungeon-master-client-0.17.2-x86_64.flatpak

It needs the freedesktop 24.08 runtime, which Flatpak fetches. The Flatpak build is complete for playing, hosting, sharing online and an OpenAI key. What its sandbox cannot do is start other programs, so the local model and agent program doors on the Story AI screen explain that they are unavailable in this build; use the AppImage, .deb or .rpm for those.

Tarball

tar -xzf open-dungeon-master-client-0.17.2-x64.tar.gz
./open-dungeon-master-client-0.17.2-x64/open-dungeon-master-client

Register the link handler yourself if you want invite links to open the app: a desktop file with MimeType=x-scheme-handler/odm; and Exec=/path/to/open-dungeon-master-client %u.

Steam Deck

Install the AppImage or the Flatpak in Desktop Mode, then add it to Steam as a non-Steam game. The app recognises the Deck: in Game Mode it starts full screen, in Desktop Mode maximised, with a title screen that fits 1280 by 800, Steam-style button hints, and controller navigation on every screen (A presses and opens Steam's keyboard on a text box, B backs out, L1 holds push to talk). Settings, Steam Deck and controllers, has Auto, On and Off; the launch options --steam-deck and --no-steam-deck decide for one shortcut and survive an update's restart.

Wayland, keyrings and Bluetooth

Runs on Wayland and X11. If the window comes up blank on an unusual GPU driver, try --disable-gpu once.
Sign-in tokens are stored through the system keyring when one is running (GNOME Keyring, KWallet). On a box with none, they are kept in a marked plain form in the app's data folder.
Pixels dice pair through the app's own Bluetooth chooser; BlueZ must be running.

Where things live

What	Where
Your device world, saved servers, sign-ins	`~/.config/open-dungeon-master-client` (Flatpak: `~/.var/app/<id>/config/open-dungeon-master-client`)
The device world's database and key	`.../open-dungeon-master-client/data`
The world's uploads, generated pictures and sound library	`.../open-dungeon-master-client/local-server/public`
Logs	`local-server.log`, `tunnel.log` in that folder

First launch.