NixOS Configuration for Dell Inspiron 3501#

A hyper-organized, flake-based NixOS configuration for a Dell Inspiron 3501 laptop with Intel Core i3-1115G4.

📁 Structure#

dotfiles-nix/
├── flake.nix                    # Main flake configuration
├── hosts/                       # Host-specific configurations
│   ├── README.md               # Guide for adding new hosts
│   └── laptop/                 # Dell Inspiron 3501 configuration
│       ├── default.nix         # Main host configuration
│       └── hardware-configuration.nix  # Hardware-specific settings
├── wallpapers/                  # Wallpaper images
│   └── wallpaper.jpg           # Default wallpaper
├── modules/                     # Reusable NixOS modules
│   ├── desktop.nix             # Desktop environment (GNOME)
│   ├── packages.nix            # System packages (uses options where possible)
│   ├── services.nix            # System services
│   └── gaming.nix              # Steam and gaming setup
└── home/                        # Home Manager configuration
    ├── home.nix                # Main home-manager config
    └── programs/
        ├── git.nix             # Git configuration
        ├── zsh.nix             # Zsh shell setup
        ├── starship.nix        # Starship prompt
        ├── fastfetch.nix       # Fastfetch config
        ├── gnome.nix           # GNOME settings & wallpaper
        └── vscode.nix          # VSCode settings

🏗️ Architecture#

Hosts Directory#

This configuration uses a hosts-based architecture for easy multi-system management:

Each physical machine gets its own directory under hosts/
Host-specific settings (hostname, hardware config) are isolated
Shared modules (desktop, packages, services) are imported by each host
Easy to add new machines - see hosts/README.md for details

Options vs System Packages#

This configuration follows NixOS best practices by using declarative options instead of just adding packages:

✅ Good (Using Options):

programs.firefox.enable = true;
programs.steam.enable = true;

❌ Less Ideal (Only System Packages):

environment.systemPackages = with pkgs; [ firefox steam ];

Why Options are Better:

More declarative and clear
Provides additional configuration options
Better integration with NixOS
Enables/disables related services automatically
Some programs require options (e.g., Steam needs firewall rules)

When to Use System Packages:

When no official NixOS option exists for the program
For simple utilities that don't need configuration
See modules/packages.nix for our approach

🖥️ Hardware Specifications#

Model: Dell Inspiron 3501
CPU: Intel Core i3-1115G4 (11th Gen Tiger Lake)
RAM: 8GB DDR4-3200
Storage: 256GB PCIe NVMe SSD (Toshiba BG4)
Graphics: Intel UHD Graphics (integrated)
Display: 15.6" FHD (1920x1080) non-touch
WiFi: Intel 9462AC
Battery: 42Wh 3-cell

📦 Included Software#

System Tools#

git - Version control (via programs.git)
fastfetch - System information
starship - Modern shell prompt
zsh - Z Shell (via programs.zsh)

Applications#

Firefox - Web browser (via programs.firefox)
VSCode - Code editor with extensions (via programs.vscode)
Spotify - Music streaming
Discord - Communication
Steam - Gaming platform (via programs.steam with GameMode)
Prism Launcher - Minecraft launcher

Desktop Environment#

GNOME - Default desktop environment
GDM - Display manager

🚀 Installation#

Option A: Switching from Stock NixOS (Recommended)#

If you already have NixOS installed and want to switch to this configuration:

Enable flakes and git (if not already enabled):

# Edit /etc/nixos/configuration.nix and add
nix.settings.experimental-features = [ "nix-command" "flakes" ];

# Build and switch
sudo nixos-rebuild switch

# Temporarily enable git
nix-shell -p git

Backup your current configuration:

sudo cp -r /etc/nixos /etc/nixos.backup

Clone this repository:

cd /tmp
git clone https://github.com/ewanc26/dotfiles-nix
cd dotfiles-nix

Generate and update hardware configuration:

# Generate fresh hardware config
sudo nixos-generate-config --show-hardware-config > hosts/laptop/hardware-configuration.nix

# Make sure file permissions are correct
sudo chown $USER:users hosts/laptop/hardware-configuration.nix

Customize the configuration:
- Edit hosts/laptop/default.nix: Update the hostname if needed
- Edit home/programs/git.nix: Set your git username and email
- Review modules/packages.nix: Add or remove packages as needed
Test the configuration (optional but recommended):
```
sudo nixos-rebuild test --flake .#laptop
```
This will apply the configuration temporarily without making it permanent. If something goes wrong, just reboot to go back to your old config.

Apply the configuration:

sudo nixos-rebuild switch --flake .#laptop

Move configuration to /etc/nixos (optional but recommended):

sudo rm -rf /etc/nixos/*
sudo cp -r * /etc/nixos/
sudo chown -R root:root /etc/nixos

Reboot and enjoy:
```
sudo reboot
```

Option B: Fresh Installation#

If you're installing NixOS from scratch:

Boot NixOS installer and partition your disk:

# Example partitioning (adjust as needed)
sudo parted /dev/nvme0n1 -- mklabel gpt
sudo parted /dev/nvme0n1 -- mkpart ESP fat32 1MiB 512MiB
sudo parted /dev/nvme0n1 -- set 1 esp on
sudo parted /dev/nvme0n1 -- mkpart primary 512MiB 100%

# Format partitions
sudo mkfs.fat -F 32 -n boot /dev/nvme0n1p1
sudo mkfs.ext4 -L nixos /dev/nvme0n1p2

# Mount
sudo mount /dev/disk/by-label/nixos /mnt
sudo mkdir -p /mnt/boot
sudo mount /dev/disk/by-label/boot /mnt/boot

Clone this repository:

cd /mnt/etc/nixos
sudo nix-shell -p git
sudo git clone https://github.com/ewanc26/dotfiles-nix .

Generate hardware configuration:

sudo nixos-generate-config --show-hardware-config > hosts/laptop/hardware-configuration.nix

Customize git config in home/programs/git.nix:
- Update userName and userEmail
Install NixOS:
```
sudo nixos-install --flake .#laptop
```
Reboot and login with your user account.

🔄 Updating the System#

After making changes to the configuration:

# Rebuild and switch to the new configuration
sudo nixos-rebuild switch --flake .#laptop

# Update flake inputs to get latest packages
nix flake update

# Then rebuild
sudo nixos-rebuild switch --flake .#laptop

Useful Commands#

# Rebuild and switch
sudo nixos-rebuild switch --flake .#laptop

# Rebuild for next boot (doesn't switch immediately)
sudo nixos-rebuild boot --flake .#laptop

# Test configuration without making it default
sudo nixos-rebuild test --flake .#laptop

# Update flake inputs
nix flake update

# Clean up old generations (keeps last 7 days)
sudo nix-collect-garbage --delete-older-than 7d

# List system generations
sudo nix-env --list-generations --profile /nix/var/nix/profiles/system

🖥️ Multi-Host Setup#

This configuration is designed to support multiple machines. To add a new host:

See the detailed guide: hosts/README.md

Quick steps:

# Create new host directory
mkdir -p hosts/my-desktop

# Generate hardware config
sudo nixos-generate-config --show-hardware-config > hosts/my-desktop/hardware-configuration.nix

# Copy and customize default.nix from laptop
cp hosts/laptop/default.nix hosts/my-desktop/

# Edit the hostname and other settings
nano hosts/my-desktop/default.nix

# Add to flake.nix (see hosts/README.md for example)
nano flake.nix

Build the new host:

sudo nixos-rebuild switch --flake .#my-desktop

🎨 Customization#

Change Desktop Environment#

Edit modules/desktop.nix to use a different DE/WM. For example, to use KDE Plasma:

services.xserver = {
  enable = true;
  displayManager.sddm.enable = true;
  desktopManager.plasma5.enable = true;
};

Add More Packages#

Using Options (Preferred)#

Edit modules/packages.nix and add to the programs section:

programs = {
  neovim.enable = true;  # Uses NixOS option
};

Using System Packages (When No Option Exists)#

environment.systemPackages = with pkgs; [
  my-custom-package  # No official option available
];

Modify Shell Configuration#

Edit home/programs/zsh.nix for shell aliases and settings.

Change Wallpaper#

The wallpaper is configured in home/programs/gnome.nix:

Add your new wallpaper image to the wallpapers/ directory

Update the file reference in home/programs/gnome.nix:

home.file.".config/wallpapers/wallpaper.jpg" = {
  source = ../../wallpapers/your-new-wallpaper.jpg;
};

Run sudo nixos-rebuild switch --flake .#laptop to apply

📝 Notes#

First Boot: The first boot may take a while as Nix downloads and builds everything.
Updates: Run nix flake update periodically to update your packages.
Rollbacks: If something breaks, you can select an older generation from the boot menu.
Garbage Collection: Run sudo nix-collect-garbage --delete-older-than 7d regularly to free up disk space.
Flakes: This configuration uses Nix flakes for reproducibility and easier dependency management.
Options Over Packages: We use programs.*.enable options instead of environment.systemPackages where possible for better integration.

🔧 Troubleshooting#

Boot Issues#

Check that UUIDs in hosts/laptop/hardware-configuration.nix match your actual partitions
Try booting from an older generation in the boot menu
Use sudo nixos-rebuild test --flake .#laptop to test changes before making them permanent

Graphics Issues#

Intel graphics should work out of the box
If you experience issues, check hardware-configuration.nix graphics settings

WiFi Not Working#

Ensure Intel WiFi firmware is loaded: lsmod | grep iwlwifi
Check NetworkManager status: systemctl status NetworkManager

Home Manager Issues#

If home-manager fails to build, try rebuilding the whole system: sudo nixos-rebuild switch --flake .#laptop
Check for syntax errors: nix flake check