# Installation

with disko-install

```sh
sudo nixos-generate-config --root /tmp/config --no-filesystems
sudo nix run 'github:nix-community/disko/latest#disko-install' -- --flake '/tmp/config/etc/nixos#mymachine' --disk main /dev/sda
sudo nix run 'github:nix-community/disko/latest#disko-install' -- --flake "https://codeberg.org/muon/home#$(hostname)" --disk crypted /dev/disk/by-diskseq/1
```


without disko-install

```sh
sudo nix --experimental-features "nix-command flakes" run github:nix-community/disko/latest -- --mode destroy,format,mount hosts/$(hostname)/disk-config.nix
sudo mount -o subvol=/ /dev/mapper/crypted /mnt
sudo btrfs subvolume snapshot -r /mnt/root /mnt/root-blank
sudo nixos-generate-config --root /mnt
mkdir -p /mnt/home/muon/src
cd /mnt/home/muon/src
git clone https://codeberg.org/muon/home
cp /mnt/etc/nixos/hardware-configuration.nix /mnt/home/muon/src/home/hosts/$(hostname)/
sudo nixos-install --root /mnt --no-root-passwd --flake /mnt/home/muon/src/home#$(hostname)
sudo umount -R /mnt
sudo cryptsetup close /dev/mapper/crypted
```

# Impermanence

## Erasure

```nix
  boot.initrd.postResumeCommands = lib.mkAfter ''
    mkdir /btrfs_tmp
    mount /dev/mapper/crypted /btrfs_tmp
    if [[ -e /btrfs_tmp/root ]]; then
        mkdir -p /btrfs_tmp/old_roots
        timestamp=$(date --date="@$(stat -c %Y /btrfs_tmp/root)" "+%Y-%m-%-d_%H:%M:%S")
        mv /btrfs_tmp/root "/btrfs_tmp/old_roots/$timestamp"
    fi

    delete_subvolume_recursively() {
        IFS=$'\n'
        for i in $(btrfs subvolume list -o "$1" | cut -f 9- -d ' '); do
            delete_subvolume_recursively "/btrfs_tmp/$i"
        done
        btrfs subvolume delete "$1"
    }

    for i in $(find /btrfs_tmp/old_roots/ -maxdepth 1 -mtime +30); do
        delete_subvolume_recursively "$i"
    done

    btrfs subvolume create /btrfs_tmp/root
    umount /btrfs_tmp
  '';
```