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NullString1 edited this page Jan 13, 2026 · 2 revisions

Adding Applications

Complete guide to adding, removing, and managing applications in NullOS.

Overview

NullOS manages applications through two main systems:

  1. NixOS (System-level) - Applications available to all users
  2. Home Manager (User-level) - User-specific applications and configs

Key Difference:

  • System packages = Installed globally, requires sudo to rebuild
  • Home packages = User-specific, no sudo needed

Quick Reference

System Applications

File:modules/software/packages.nix
Rebuild:sudo nixos-rebuild switch --flake .#hostname

Home Manager Applications

File:home/default.nix
Rebuild:home-manager switch --flake .

Adding System Applications

Step 1: Find the Package

Search for packages on https://search.nixos.org/packages

Or use command line:

nix search nixpkgs htop
nix search nixpkgs firefox

Step 2: Edit packages.nix

Open modules/software/packages.nix:

{config,pkgs, ... }:
{environment.systemPackages=withpkgs;[# Existing packages...vimgitwget# Add your new package herehtopbtopneofetch];}

Step 3: Rebuild

sudo nixos-rebuild switch --flake .#yourhostname

Example: Adding Development Tools

environment.systemPackages=withpkgs;[# Developmentgcccmakegnumakepython3nodejsrustup# Databasespostgresqlredis# Toolsdocker-composekubectl];

Adding Home Manager Applications

Step 1: Edit home/default.nix

Open home/default.nix:

{config,pkgs, ... }:
{home.packages=withpkgs;[# Existing packages...firefoxdiscord# Add your packagesspotifyobs-studiogimpvlc];}

Step 2: Rebuild Home Manager

home-manager switch --flake .

Or rebuild entire system (includes home-manager):

sudo nixos-rebuild switch --flake .#yourhostname

Example: Adding Creative Software

home.packages=withpkgs;[# Image Editinggimpinkscapekrita# Video Editingkdenliveobs-studio# Audioaudacitylmms# 3Dblender];

Removing Applications

Remove System Package

Edit modules/software/packages.nix and delete the line:

environment.systemPackages=withpkgs;[vimgit# htop # Removed];

Rebuild:

sudo nixos-rebuild switch --flake .#yourhostname

Remove Home Manager Package

Edit home/default.nix and delete the line:

home.packages=withpkgs;[firefox# discord # Removed];

Rebuild:

home-manager switch --flake .

Program Modules vs Packages

Some applications have dedicated program modules with additional configuration.

Using Program Modules

Instead of just adding to packages, use program configuration:

# In home/default.nix or dedicated fileprograms.firefox={enable=true;profiles.default={settings={"browser.startup.homepage"="https://nixos.org";"privacy.trackingprotection.enabled"=true;};};};programs.git={enable=true;userName="Your Name";userEmail="you@example.com";extraConfig={init.defaultBranch="main";};};programs.vscode={enable=true;extensions=withpkgs.vscode-extensions;[jnoortheen.nix-idegithub.copilot];};

Benefits:

  • Declarative configuration
  • Version control your settings
  • Easy to replicate on new machines

Package Sources

Regular Packages

Most packages from nixpkgs:

home.packages=withpkgs;[firefoxvlchtop];

Stable Packages

Use stable channel for older, tested versions:

home.packages=[pkgs.stable.firefox# From nixos-25.05];

Unfree Packages

NullOS already enables unfree packages. If you need to verify:

# In flake.nix (already configured)config.allowUnfree=true;

Examples of unfree packages:

  • vscode
  • discord
  • spotify
  • steam
  • nvidia-x11

Installing from Different Sources

From Flake Input

# In flake.nix inputsinputs.my-app.url="github:username/my-app";# In configuration moduleenvironment.systemPackages=[inputs.my-app.packages.${pkgs.system}.default];

From GitHub (Fetch)

home.packages=[(pkgs.fetchFromGitHub{owner="username";repo="repo";rev="commit-hash";sha256="sha256-hash";})];### Build from SourceCreateacustomderivation:
```nix# packages/my-app.nix{pkgs}:
pkgs.stdenv.mkDerivation{pname="my-app";version="1.0.0";src=pkgs.fetchurl{url="https://example.com/my-app.tar.gz";sha256="...";};buildInputs=[pkgs.gcc];installPhase='' mkdir -p $out/bin cp my-app $out/bin/ '';}

Import and use:

home.packages=[(pkgs.callPackage./packages/my-app.nix{})];

Application Recommendations

For a curated list of recommended applications by category, please refer to:

Flatpak Applications

NullOS includes Flatpak support.

Installing Flatpak Apps

# Search
flatpak search spotify
# Install
flatpak install flathub com.spotify.Client
# Run
flatpak run com.spotify.Client

Adding Flatpak Declaratively

Edit modules/software/flatpak.nix:

services.flatpak.enable=true;# Then manually install or use home-manager's nix-flatpak

With nix-flatpak (requires adding as input):

services.flatpak.packages=["com.spotify.Client""com.discordapp.Discord"];

AppImages

Running AppImages

home.packages=[pkgs.appimage-run];

Run AppImages:

appimage-run MyApp.AppImage

Making AppImages Executable

chmod +x MyApp.AppImage
./MyApp.AppImage

Managing Application Versions

Pinning Package Versions

Use specific nixpkgs commit:

# In flake inputsinputs.nixpkgs-old.url="github:nixos/nixpkgs/commit-hash";# Use old versionhome.packages=[inputs.nixpkgs-old.legacyPackages.${pkgs.system}.oldpackage];

Using Overlays

Create custom package versions:

# In flake.nix overlaysoverlays=[(final: prev: {myapp=prev.myapp.overrideAttrs(old: {version="2.0.0";src=prev.fetchurl{url="https://example.com/myapp-2.0.0.tar.gz";sha256="...";};});})];

Application Configuration

Creating Dedicated Config Files

For better organization, create separate files:

home/
├── firefox.nix
├── vscode.nix
├── discord.nix
└── default.nix

Example:home/firefox.nix

{config,pkgs, ... }:
{programs.firefox={enable=true;profiles.default={bookmarks=[{name="NixOS";url="https://nixos.org";}];settings={"browser.startup.homepage"="about:blank";"privacy.trackingprotection.enabled"=true;};};};}

Import in home/default.nix:

imports=[./firefox.nix./vscode.nix];

Application Launchers

Applications are automatically available in Rofi after installation.

Desktop Entries

Applications with .desktop files appear automatically.

Manual Desktop Entry

For apps without desktop entries:

# In home/default.nixxdg.desktopEntries.myapp={name="My Application";genericName="App";exec="myapp";terminal=false;categories=["Application"];};

Troubleshooting

Package Not Found

  1. Search with correct name:
nix search nixpkgs package-name

  1. Check spelling and availability

  2. May be unfree - ensure allowUnfree = true

Application Won't Start

  1. Check if installed:
which application-name
  1. Run from terminal to see errors:
application-name
  1. Check logs:
journalctl --user -e

Version Conflicts

Use overlays to override conflicting versions:

nixpkgs.overlays=[(final: prev: {package=prev.package.override{dependency=prev.dependency_v1;};})];

Missing Dependencies

Some packages need additional dependencies:

environment.systemPackages=withpkgs;[myapp# Required dependencieslib1lib2];

Best Practices

  1. Organize by Category - Group related packages
  2. Comment Your Additions - Note why you installed something
  3. Use Program Modules - When available, for better config
  4. Separate User/System - System packages for all users, home for personal
  5. Test Before Committing - Build first, then commit to git
  6. Remove Unused - Keep your package list clean

Advanced: Creating Custom Modules

For complex applications, create a module:

# modules/software/my-app.nix{config,lib,pkgs, ... }:
withlib;letcfg=config.programs.myapp;in{options.programs.myapp={enable=mkEnableOption"My Application";package=mkOption{type=types.package;default=pkgs.myapp;description="Package to use";};settings=mkOption{type=types.attrs;default={};description="Application settings";};};config=mkIfcfg.enable{environment.systemPackages=[cfg.package];environment.etc."myapp/config.json".text=builtins.toJSONcfg.settings;};}

Import in modules/software/default.nix:

imports=[./my-app.nix];

Use in configuration:

programs.myapp={enable=true;settings={theme="dark";};};

Updating Applications

Update All Packages

# Update flake inputs
nix flake update
# Rebuild
sudo nixos-rebuild switch --flake .#hostname

Update Specific Input

nix flake lock --update-input nixpkgs

Check for Updates

nix flake metadata

Next Steps

Clone this wiki locally