prex

Run Windows executables in Steam Proton prefixes

List all installed games

prex ls
1245620 ELDEN RING      default
1888160 ARMORED CORE VI FIRES OF RUBICON      proton_experimental
2050650 Resident Evil 4 default
2622380 ELDEN RING NIGHTREIGN   default

List all users

prex users
59710912        Dark Empath Amogus
1516607315      zilfeejel

List currently running games

prex ps
1245620 ELDEN RING

Run an installer

prex run 2050650 ~/Downloads/Fluffy\ Mod\ Manager-818-3-068-1765672670/Modmanager.exe

Reuse a running app (single-instance apps)

prex run --single-instance 489830 "/games/steam/steamapps/compatdata/489830/pfx/drive_c/Program Files/Black Tree Gaming Ltd/Vortex/Vortex.exe" --download nxm://example

NXM handling (mod manager registration)

Register a mod manager for a game (the exe must live inside that game's prefix):

prex mm add 489830 "/games/steam/steamapps/compatdata/489830/pfx/drive_c/Program Files/Black Tree Gaming Ltd/Vortex/Vortex.exe"
prex mm ls
489830  The Elder Scrolls V: Skyrim Special Edition  inactive  /games/steam/steamapps/compatdata/489830/pfx/drive_c/Program Files/Black Tree Gaming Ltd/Vortex/Vortex.exe
prex mm set-active 489830

Remove a mod manager registration:

prex mm remove 489830

Handle NXM links with the active mod manager:

prex nxm "nxm://skyrimspecialedition/mods/12345"

Example desktop entry:

[Desktop Entry]
Name=Prex NXM Handler
Comment=Handle NXM links for active mod manager
Type=Application
NoDisplay=true
MimeType=x-scheme-handler/nxm;
Exec=prex nxm %u

Print a game's Proton prefix path (pfx)

prex path 2050650
/games/steam/steamapps/compatdata/2050650/pfx
cd "$(prex path 2050650)"

Start something alongside a running game

prex attach 1245620 "/games/steam/steamapps/compatdata/1245620/prex/drive_c/Program Files/Cheat Engine/Cheat Engine.exe"

Hack to bypass gamescope

prex attach --bypass-gamescope 1245620 "/games/steam/steamapps/compatdata/1245620/prex/drive_c/Program Files/Cheat Engine/Cheat Engine.exe"

Launch another executable while preserving Steam launch options

Keeps any launch options you set in Steam, for example:

LD_PRELOAD= gamescope -f -H 1440 -h 1440 -r 75 --mangoapp -- env LD_PRELOAD="$LD_PRELOAD" gamemoderun %command%

Seamless Co-op for Elden Ring example

prex launch 1245620 --user-id 59710912 "Game/ersc_launcher.exe" 

Shell completions

Dynamic completions are generated at shell runtime. These examples source the generated script on startup:

Bash

echo 'source <(COMPLETE=bash prex)' >> ~/.bashrc

Zsh

echo 'source <(COMPLETE=zsh prex)' >> ~/.zshrc

Supported shells: bash, zsh, fish, elvish, (powershell ಠ_ಠ).