What's new in cpmm

The first public alpha of cpmm, a Cyberpunk 2077 mod manager for Linux and Proton, with a command-line tool and a controller-friendly GUI that works in Steam’s Game Mode.

Alpha. Expect rough edges and back up your saves. Bug reports are welcome in Issues.

Highlights

• Your game folder stays untouched. Mods are staged one folder per mod and shown to the game through an overlay (overlayfs). It needs no root and no FUSE, and copies nothing into the game folder. cpmm run -- %command% in Steam’s launch options mounts the overlay only for the game, so Steam updates and “verify files” still see the original install.
• Installs from Nexus Mods:
  • nxm:// “Mod Manager Download” links, the built-in Nexus browser, manual downloads (from a Downloads list), and mods you tracked on the site
  • downloads are checked against Nexus’s SHA-256 manifest
  • FOMOD installers, with a step-by-step chooser; your choices are reused on updates
  • Nexus Collections, installed into their own profile with the curator’s options and load-order rules
• Requirements. Checked at every install, with one-click fixes for missing or disabled ones, and the option to ignore one on purpose.
• Health and load order:
  • an automatic load order that respects requirements and your own rules
  • conflict views for files, archive resources and redscript methods, with per-file hide/prefer
  • a health check for crash risks, with one-click remedies
  • crash triage that shows what changed since the last clean session
• Safety net:
  • updated or replaced versions are kept for rollback
  • “undo update” reverts a whole update run
  • snapshots of your save games before risky changes
• Profiles, each with its own mod list and its own saves.
• Updates for the exact Nexus file you installed, with a “What’s new” changelog per mod.
• mod.io: sees the mods you subscribed to in the in-game Mods menu, and flags clashes with mods cpmm installed.
• Steam Deck / ROG Ally:
  • cpmm steam-shortcut adds the GUI to your Steam library, with artwork
  • the GUI can be driven entirely with a gamepad, including in the Nexus browser
• First-run setup in the GUI, or cpmm setup.

Install

1. Download cpmm-0.1.0-alpha-linux-x86_64.tar.gz, and check it against the .sha256 file.
2. Extract it, and put cpmm and cpmm-gui side by side somewhere on your PATH, e.g. ~/.local/bin.
3. Run cpmm-gui (or cpmm setup), then paste the line from cpmm launch-options into the game’s Steam launch options.

Requirements:

• Linux 6.8 or newer, with unprivileged user namespaces enabled
• 7z
• cpmm’s data folder on the same filesystem as the game

Known limitations

• Personal Nexus API key. cpmm isn’t registered with Nexus Mods yet, so it needs your personal API key (in ~/.config/nexusmods/apikey). Nexus allows that only for personal use and testing. Registration and Single Sign-On are planned before a wider release.
• Premium for one-click downloads. Installing straight from the API needs Nexus Premium. Free accounts use the site’s “Mod Manager Download” buttons (nxm:// links).
• Linux x86_64 only.