Stop and disable systemd units before removing packages

$ aur_helper -S systemd-cleanup-pacman-hook

Just remove packages as usual using pacman, and it will be taken care of automatically for you.

The provided hook doesn't remove the override files (e.g. drop-in files) for the unit.

To also remove those automatically, modify the hook to use --revert option:

# install -Dm644 /usr/share/libalpm/hooks/systemd-cleanup.hook /etc/pacman.d/hooks/systemd-cleanup.hook
# sed -i '/^Exec =/s/$/ --revert/' /etc/pacman.d/hooks/systemd-cleanup.hook

There might be existing broken symlinks to deleted systemd units in your system (before installing this hook).

You can use the command below to check for them:

# find /etc/systemd/{system,user} -xtype l