nixos-cfg#

NixOS Configuration - Modular, Scalable & Minimal

Installation#

1. Boot the NixOS ISO#

Download the minimal ISO from https://nixos.org/download and flash it to a USB drive:

dd if=nixos-minimal-*.iso of=/dev/sdX bs=4M status=progress

Boot the target machine from the USB. Switch to a root shell:

sudo -i

2. Connect to the internet#

# wired — usually works automatically via DHCP
ip a

# wifi
iwctl
  station wlan0 scan
  station wlan0 connect "SSID"
  exit

3. Partition and format with disko#

⚠️ This wipes /dev/nvme0n1 completely. Make sure you are targeting the right disk.

sudo nix run --extra-experimental-features "nix-command flakes" \
  github:nix-community/disko -- \
  --mode destroy,format,mount \
  --flake github:MasterEnderman/nixos-cfg#hp-probook \
  --yes-wipe-all-disks

This creates and mounts:

- /boot — EFI partition (vfat, 512M)
- cryptroot — LUKS-encrypted btrfs partition
  - @nix → /nix
  - @persist → /persist
  - @swap → /.swapvol (16G swapfile)
- / — tmpfs (2G, wiped on every reboot)

4. Clone the config into persist#

Since /persist is now mounted and will survive across reboots, clone the repo there directly:

git clone https://github.com/MasterEnderman/nixos-cfg.git /mnt/persist/etc/nixos

5. Regenerate hardware configuration#

nixos-generate-config --root /mnt --show-hardware-config \
  > /mnt/persist/etc/nixos/modules/hosts/hp-probook/hardware-configuration.nix

Review the output before saving — make sure the initrd kernel modules look correct for your hardware.

6. Fix machine-id#

# Generate a new UUID and write it to the file
uuidgen | tee /mnt/persist/etc/machine-id

# Set correct permissions (read-only for everyone)
chmod 444 /mnt/persist/etc/machine-id

7. Install#

nixos-install --flake /mnt/persist/etc/nixos#hp-probook --root /mnt

This will ask you to set a root password at the end. Set something temporary — you can disable root login after first boot.

8. ???#

9. Commit the generated hardware config#

cd /mnt/persist/etc/nixos
git add modules/hosts/hp-probook/hardware-configuration.nix
git commit -m "add hp-probook hardware configuration"
git push

10. Reboot#

reboot

Remove the USB drive when the screen goes dark.

First boot#

What to expect#

1. systemd-boot presents the boot menu
2. You are prompted for the LUKS passphrase to decrypt the drive
3. Niri starts, noctalia-shell launches on top

First things to do#

Verify persistence is working:

findmnt | grep persist

Verify the kernel:

uname -r
# should include "cachyos" in the name

Set up SSH keys (if not restoring from backup):

ssh-keygen -t ed25519 -C "enderman@hp-probook"
# add ~/.ssh/id_ed25519.pub to GitHub

SSH keys are listed in the preservation module and will survive reboots once created.

Disable root login (recommended):

Add to modules/nixos/features/common.nix:

users.users.root.hashedPassword = "!";

Then rebuild:

sudo nixos-rebuild switch --flake /etc/nixos#hp-probook

Change your user password:

passwd enderman

Adding New Machines#

To add a new host (e.g., gaming-pc), simply create the folder and files:

modules/nixos/hosts/gaming-pc/
├── default.nix         ← Copy from hp-probook, change hostname
├── disko.nix           ← Adjust disk path (/dev/nvme0n1 vs /dev/sda)
└── hardware-configuration.nix ← Run nixos-generate-config inside mount

Then add one line to flake.nix:

nixosConfigurations = {
  hp-probook = mkHost "hp-probook";
  gaming-pc = mkHost "gaming-pc";  # ← One line!
};

Home Manager runs the SAME profile (enderman) on ALL machines. No duplication needed.

Common Commands#

# Build and test without installing
nix build .#hp-probook

# Rebuild on running system
sudo nixos-rebuild switch --flake .#hp-probook

# Rollback if something breaks
sudo nixos-rebuild switch --rollback