FredOS NixOS Configuration

Flake-based NixOS configuration for three machines, built and deployed directly from GitHub. No local config management required after initial setup.

Machines

Hostname	Description
FredOS-Gaming	AMD desktop, UEFI/systemd-boot
FredOS-Macbook	Intel laptop, UEFI/systemd-boot
FredOS-Mediaserver	Intel server, BIOS/GRUB

Structure

flake.nix                        # Flake inputs and host definitions
common.nix                       # Shared config for all hosts
hosts/
  FredOS-Gaming.nix              # Gaming-specific config
  FredOS-Macbook.nix             # Macbook-specific config
  FredOS-Mediaserver.nix         # Mediaserver-specific config
  hardware/
    FredOS-Gaming.nix            # Hardware config + bootloader
    FredOS-Macbook.nix
    FredOS-Mediaserver.nix
apps/                            # Per-app config files
settings/                        # Shared system settings (GNOME, locale, audio, etc.)
services/                        # Service definitions
home-manager/                    # Home Manager config
walls/                           # Wallpapers

Day-to-day usage

Edit files directly on GitHub, then on the machine run:

update

That's it. The alias is defined in common.nix and expands to:

sudo nixos-rebuild switch --flake github:ediblerope/nixos-config --refresh --no-write-lock-file

Nix automatically matches the running machine's hostname to the correct nixosConfigurations entry.

Other useful aliases:

clean    # sudo nix-collect-garbage -d

---

Adding a new machine

1. Fresh NixOS install

Boot the NixOS installer and complete the standard installation. Note the system.stateVersion it generates — you'll need it later.

2. Enable flakes temporarily

Add this to /etc/nixos/configuration.nix and rebuild:

nix.settings.experimental-features = [ "nix-command" "flakes" ];

sudo nixos-rebuild switch

3. Create the hardware config on GitHub

Copy the contents of /etc/nixos/hardware-configuration.nix and create hosts/hardware/FredOS-NEWHOST.nix on GitHub. Append the following to it:

networking.hostName = "FredOS-NEWHOST";

# Match what the installer configured — systemd-boot for UEFI:
boot.loader.systemd-boot.enable = true;
boot.loader.efi.canTouchEfiVariables = true;
boot.loader.systemd-boot.configurationLimit = 5;
boot.initrd.systemd.enable = true;

# For BIOS/GRUB machines instead:
# boot.loader.grub.enable = true;
# boot.loader.grub.devices = [ "/dev/sda" ]; # verify with: sudo grub-probe --target=disk /

nix.settings.experimental-features = [ "nix-command" "flakes" ];
system.stateVersion = "25.11"; # use the version the installer generated

4. Register the host in flake.nix

In flake.nix on GitHub, add to nixosConfigurations:

FredOS-NEWHOST = mkHost "FredOS-NEWHOST";

5. Add host-specific config

Create hosts/FredOS-NEWHOST.nix on GitHub for any machine-specific packages or services:

{ config, pkgs, lib, ... }:
{
  config = lib.mkIf (config.networking.hostName == "FredOS-NEWHOST") {
    # host-specific config here
  };
}

Then add it to the imports list in common.nix:

./hosts/FredOS-NEWHOST.nix

6. Switch to the flake

Run this once on the new machine with the explicit hostname:

sudo nixos-rebuild switch --flake github:ediblerope/nixos-config#FredOS-NEWHOST --refresh --no-write-lock-file

After this succeeds, the plain update alias works from then on.

---

Flake inputs

Input	Source
nixpkgs	github:NixOS/nixpkgs/nixos-unstable
home-manager	github:nix-community/home-manager
omnisearch	git+https://git.bwaaa.monster/omnisearch
zen-browser	github:0xc000022070/zen-browser-flake
nix-flatpak	github:gmodena/nix-flatpak

Notes

• hosts/hardware/ files are committed to the repo — they contain UUIDs and disk layout but no sensitive credentials
• Host-specific behaviour is gated with lib.mkIf (config.networking.hostName == "...") or lib.elem config.networking.hostName [...]
• GitHub API rate limit (60 req/hour unauthenticated) can occasionally be hit if running update many times in quick succession during active config changes — wait ~15 minutes and retry