Steam Deck · cpmm

Install cpmm in Desktop Mode, add it to your Steam library, and use it from Game Mode.

cpmm was built on a handheld. It works on Steam Deck and other Linux handhelds such as the ROG Ally, both in Desktop Mode and in Game Mode.

Install in Desktop Mode

Switch to Desktop Mode (hold the power button, then Switch to Desktop).
Open Konsole and check your kernel: uname -r should print 6.8 or newer.
Download the latest release from the download page and install it as in Install.
Run cpmm-gui and go through the setup flow.

Add cpmm to your Steam library

cpmm steam-shortcut

This adds the GUI to Steam as a non-Steam game called cpmm, with its library artwork. If Steam is running, the entry appears straight away; this needs Steam’s CEF debugger, which Decky Loader turns on. Otherwise, close Steam first and cpmm edits the shortcut files directly. Run it again to refresh the artwork, or use --remove to take the shortcut out.

Using cpmm in Game Mode

Launch cpmm from your library like any game. Everything is reachable with the controller:

Control	Action
D-pad / left stick	Move between items
A	Select
B	Back
LB / RB	Switch section
Start	Activity
Select	Refresh

Getting mods in Game Mode

Steam’s built-in browser refuses nxm:// links, so the Nexus Mod Manager Download button does nothing there. You have three alternatives:

Browse Nexus in cpmm (in the sidebar, or on the Install page). It opens nexusmods.com in a cpmm window you can drive with the controller: the right stick or D-pad moves a cursor, A clicks, the left stick scrolls, Y opens the on-screen keyboard, and Start returns to cpmm. Mod Manager Downloads are caught and installed with their requirements.
Press Track on a mod page in any browser, then run cpmm tracked --install.
Use Firefox, either as a non-Steam game or on the desktop, with cpmm registered as the nxm:// handler.

Sign in to Nexus inside cpmm’s browser with your email and password. Google and Apple sign-in usually refuse embedded browsers.