Nix package manager install (single user) on Fedora Silverblue

Nix_package_manager_on_Fedora_Silverblue.md

Nix package manager on Fedora Silverblue

Warning

Disable composefs or enable root.transient before install and use nix on Fedora Silverblue 42. Do not mix both. Use just one method. I prefer enabling root.transient.

• With composefs disabled

  sudo sed -i 's/,ro//' /etc/fstab
  
  sudo rpm-ostree kargs --append='ostree.prepare-root.composefs=0' --reboot

• With root.transient enabled

  sudo tee /etc/ostree/prepare-root.conf <<'EOL'
  [composefs]
  enabled = yes
  [root]
  transient = true
  EOL
  
  rpm-ostree initramfs-etc --reboot --track=/etc/ostree/prepare-root.conf

Install nix

curl -sSfL https://artifacts.nixos.org/nix-installer | \
    sh -s -- install ostree --explain --add-channel --persistence=/var/lib/nix

Add nix unstable channel to normal user

nix-channel --add https://nixos.org/channels/nixpkgs-unstable nixpkgs
nix-channel --update

Fix sudo

echo "Defaults  secure_path = /nix/var/nix/profiles/default/bin:/nix/var/nix/profiles/default/sbin:$(sudo printenv PATH)" | sudo tee /etc/sudoers.d/nix-sudo-env

Old way (Obsolete)

• This is a single user install.

• For multi user install and without changing selinux mode: https://gist.github.com/matthewpi/08c3d652e7879e4c4c30bead7021ff73

• Please note that these instructions are not offically supported or condoned by Nix and are not guaranteed to always work, but from my testing everything seems to work perfectly fine.

• Change SELinux mode to permissive

  sudo setenforce Permissive
  sudo sed -i 's/SELINUX=enforcing/SELINUX=permissive/' /etc/selinux/config

• Create the nix directory in a persistent location

  sudo mkdir /var/lib/nix
  sudo chown $USER:$USER /var/lib/nix

• /etc/systemd/system/mkdir-rootfs@.service

  [Unit]
  Description=Enable mount points in / for ostree
  ConditionPathExists=!%f
  DefaultDependencies=no
  Requires=local-fs-pre.target
  After=local-fs-pre.target
  
  [Service]
  Type=oneshot
  ExecStartPre=chattr -i /
  ExecStart=mkdir -p '%f'
  ExecStopPost=chattr +i /

• /etc/systemd/system/nix.mount

  [Unit]
  Description=Nix Package Manager
  DefaultDependencies=no
  After=mkdir-rootfs@nix.service
  Wants=mkdir-rootfs@nix.service
  Before=sockets.target
  After=ostree-remount.service
  BindsTo=var.mount
  
  [Mount]
  What=/var/lib/nix
  Where=/nix
  Options=bind
  Type=none
  
  [Install]
  WantedBy=local-fs.target

• Enable and mount the nix mount.

  # Ensure systemd picks up the newly created units
  sudo systemctl daemon-reload
  # Enable the nix mount on boot.
  sudo systemctl enable nix.mount
  # Mount the nix mount now.
  sudo systemctl start nix.mount

• Install Nix

  sh <(curl -L https://nixos.org/nix/install) --no-daemon

• Load Nix into your environment. Enable bash/fish/zhs completion for nix installed commands

  Load Nix into your environment. The installer modified ~/.bash_profile, but it isn't used when you start a terminal from desktop, it's only used when using a full shell login with bash -l, which doesn't happen on silverblue.

  tee --append $HOME/.bashrc <<EOF
  # Nix Package Manager
  if [ -e $HOME/.nix-profile/etc/profile.d/nix.sh ]; then
      source $HOME/.nix-profile/etc/profile.d/nix.sh;
  fi
  EOF

• Links:

  • https://tecadmin.net/how-to-disable-selinux-on-fedora/
  • https://gist.github.com/matthewpi/08c3d652e7879e4c4c30bead7021ff73
  • https://gist.github.com/queeup/26e36c6e3e701c0ba96c17dc5e5251be

many thanks, it helped!