hetzner-dedicated/zfs: Install zfs from source

hosters/hetzner-dedicated/zfs-uefi-nvme-nixos.sh

@@ -26,20 +26,27 @@
 # * exports of env vars are added throughout the script in case you want to run it manually
 export LC_ALL=C
 
-# WARNING: on 2023/07/16 the rescue system of hetzner boots with kernel 6.3.7 which
+set -euox pipefail
+
+# ORIGINAL WARNING: on 2023/07/16 the rescue system of hetzner boots with kernel 6.3.7 which
 # is by default not supported by the latest debian package. You need to update to debian
 # unstable to proceed with the zfs installation.
 
-cat > /etc/apt/preferences.d/90_zfs <<EOF
-Package: libnvpair1linux libnvpair3linux libuutil1linux libuutil3linux libzfs2linux libzfs4linux libzpool2linux libzpool4linux spl-dkms zfs-dkms zfs-test zfsutils-linux zfsutils-linux-dev zfs-zed
-Pin: release n=bullseye-backports
-Pin-Priority: 990
-EOF
+# NEW WARNING: Upgrading to unstable is too much work, maybe just downloading zfs and building it is easier.
 
-apt update -y
-apt install -y dpkg-dev linux-headers-$(uname -r) linux-image-amd64 sudo parted zfs-dkms zfsutils-linux
+apt update
+apt install -y dpkg-dev linux-headers-$(uname -r) linux-image-amd64 sudo parted
 
-set -euox pipefail
+cd "$(mktemp -d)"
+wget "$(curl -Ls https://api.github.com/repos/openzfs/zfs/releases/latest| grep -E "browser_download_url.*\.tar.gz\"$"| cut -d '"' -f 4)"
+apt update
+apt install libssl-dev uuid-dev zlib1g-dev libblkid-dev -y
+tar xfv zfs*.tar.gz && rm zfs*.tar.gz
+cd zfs*
+./configure && make -j "$(nproc)"
+make install
+ldconfig
+modprobe zfs
 
 # hetzner has some weird symlinks to make you install zfs with their script
 rm /usr/local/sbin/zfs || true
@@ -176,9 +183,6 @@ mdadm --zero-superblock --force $DISK2-part3 || true
 # See https://github.com/NixOS/nixpkgs/issues/62444
 udevadm trigger
 
-# Sometimes the zfs module is not loaded
-modprobe zfs
-
 # taken from https://nixos.wiki/wiki/NixOS_on_ZFS
 # somehow there is a weird symlink in the default zfs
 zpool create -O mountpoint=none \