NOMM (Native Open Mod Manager)

The project

NOMM is a stupid simple, super clean "native" (as in it runs on Linux without having to use translation tools...) mod manager for Linux. The goal here is to keep the setup really simple for idiots like me who don't need complex features and all that jazz. Just a few clicks, a clean, modern interface, and you're done :)

Don't come here expecting it to manage mods for something like Skyrim. There are specific tools for that (see NaK or Jackify).

Instead, think of NOMM as more of a general purpose tool for most games that just need you to point to a directory and extract some zip files.

Warning

This project is partially made with the help of Gemini (especially on the GUI side of things).

If you hate AI, that makes two of us, however, I would never have been able to make something like this without it (simply because of the amount of work and research it would have required).
I want to be clear that even if coding is not my job, I do have a computer science background and understand all of the code that Gemini has created.

My Guiding Principles

• No Ads
• No Telemetry
• No User Account Requirement
• Clean & Modern UI/UX
• Beginner-friendly
• Fully open

How can you add support for a game?

One of the main ideas behind this project is that games are defined by easy to create config .yaml files. This means that anyone can create a simple yaml for their game and submit it to the project with little to no coding knowledge and the tool will automate the rest.

This yaml file will need to be placed in [nomm root folder]/default_game_configs For instance, if you would want to add support for Stadew Valley, you would create a [nomm root folder]/default_game_configs/stardew_valley.yaml file.

In that yaml you will need to define some basic information for it to be recognised:

Defining basic information

• Name

name: 'Metal Gear Solid Δ: Snake Eater' # the name of the game, with any symbols, spaces and whatnot kept intact

• Steam App ID

steam_id: 2417610 # the steam app id, you can find this on: https://steamdb.info/

• Steam Folder Name

steam_folder_name: "MGSDelta" # the steam folder name for the game in your steamapps folder - only useful if the game name and folder name are different

• Nexus Mods ID

nexus_id: "metalgearsoliddeltasnakeeater" # the nexus game key - used for nexus downloads (generally the game name with no symbols and all attached, but please check before submitting)

• GOG Store ID(s)

gog_id: 1207666893 # the gog store id

Note

You can remove gog_id if the game is not on the GOG store.

• Load order

load_order_path: mods/mod_load_order.txt # for games with a text-editable load order, you can specify a path and a button will appear in the app to edit it directly.

Defining where mods should be enabled in the game folders

mods_path can be defined in two ways:

• "Legacy" (This works in all versions of NOMM)

mods_path: mods/ # the path where the mods need to be installed when they are enabled

• "Multiple" (only available in Nomm versions > 0.6.0)

mods_path: 
- path: "{user_data_path}/drive_c/users/steamuser/AppData/Local/Larian Studios/Baldur's Gate 3/Mods"
  name: Default
  description: "Used for most mods, the in game mod manager included"
- path: "{game_path}/"
  name: Native
  description: "Used for native mods that require the Native mod loader, such as the 'Native Camera Tweaks' mod."

Note

mods_path can contain as many paths as you want, but the goal here is not to add a path for a single mod. If there is only one mod using that path, chances are it is a library mod that should be installed with the utilities section below.

Essential utilities

Nomm lets you define some "essential utilities" that will be used to mod a game. Think libraries or modding tools that have their own needs in terms of installation complexity that don't fit with other "standard" mods and generally require additional actions to get them set up.

essential-utilities: # this lets you define things such as mod loaders or essential utilities
  darktide-mod-loader: # you can have multiple ones, each one needs its own unique key
    name: Darktide Mod Loader # the name of the tool
    creator: Talon-d # the creator of the tool
    creator-link: https://github.com/talon-d # a link to the creator's page, portal, social, whatever
    whitelist: d8input.dll # a list of files that should ONLY be included (optional)
    blacklist: d7input.dll # a list of files that should NOT be included (optional)
    source: "https://github.com/talon-d/darktideML-4linux/releases/download/1.5/darktideML-4linux1-5.zip" #the actual thing we'll need to download
    utility_path: "" # where the utility needs to be extracted to
    enable_command: "sh handle_darktide_mods.sh --enable" # any command that needs to be run (from the root of the game folder) to enable the mod loader

"Roadmap"

Phase 1 Development Progress:

• Auto-detect Steam libraries
• Auto-detect Steam library games
• Obtain cool images for game tiles from Steam cache folder
• Display results in a super clean library-style window
• Let user choose a downloads folder location
• Create a whole new window with a cool header from Steam cache folder
• Associate app w/ nexusmods download links
• Let user navigate downloaded mods and delete downloaded mods
• Figure out how mod staging and symlinks and whatnot work because I have no idea
• Let user enable/disable mods
• Prepare "essential utilities" section in game config file that lets the community define some essential custom tools that are needed for a game to work, so that the process is easier for people who just want to mod the game (i.e. SKSE, Darktide mod loader, that kind of stuff)
• Let user launch the game directly from the interface
• Add a button to return to launcher from the main window

Phase 2 Development Progress:

• Rudimentary FOMOD support
• Add mod update checker
• Let user skip launcher and go straight to game
• Figure out how to create a flatpak for the app
• Add language-specific strings
• Let user define load orders
• Add support for GOG libraries / games (through Heroic)
• Add support for Epic libraries / games (through Heroic)
• Detect conflicts

Phase 3 Development Progress:

• Manage conflicts (for sure this will be hard without an actually good developer)
• Review access rights to be more restrictive
• Make a Flathub build
• Handle more complex FOMOD, and handle them cleanly

Bonus (nice to have)

• Game profiles?
• ???

Installing/Running

The easiest way to run the app is with flatpak!

To do so :

1. Go to the releases tab.
2. Expand the Assets box of the latest version
3. Click on the nomm.flatpak file to download it
4. Once downloaded, if you have KDE/GNOME you may simply double click the file. This should boot up KDE Discover or Gnome Software.
5. Once there you should have a button to install the app, click it.
6. Once installed, you will see a Launch or Run button appear, click it.

And you're done!

For more advanced users (those who prefer the console or may not have a standard distro)

You may install and run the flatpak via command line: 4. flatpak install nomm.flatpak 5. flatpak run flatpak run com.nomm.Nomm

From now on when you want to launch it you can just look for it in your start menu (by typing "nomm")

Building

Dependencies

The app is built with:

• Python (3.14) -> ...Python...
• GTK (>4.0) -> UI framework
• Libadwaita -> UI framework
• Requests -> requests to nexusmods, gog, epic, etc.
• Unrar -> extraction of mods in rar format
• vdf -> read steam config files
• PyYAML -> read and write yaml files

Prerequisites

• Obviously to build a flatpak you need to have a distro with flatpak support (most of them do) -> this should normally include the flatpak-builder utility
• You need to download the flatpak-pip-generator tool

Building the app

1. Make the build.sh file executable (if you don't know how to do this see here)
2. Place your flatpak-pip-generator.py file at the root of the app's directory
3. Run ./build.sh
4. Wait for flatpak to be built
5. You should now have a nomm.flatpak file in the directory
6. To install your newly obtained flatpak, follow the steps in the "Installing/Running" section above