nix-config/.archlinux/install-scripts/003-configure

#!/bin/sh
#
# Core system configs
#
# https://wiki.archlinux.org/index.php/Installation_guide

set -xe

# Generate the fstab file (so the filesystem is mounted on boot)
genfstab -U /mnt > /mnt/etc/fstab

# Set the timezone
arch-chroot /mnt ln -sf /usr/share/zoneinfo/America/New_York /etc/localtime

# Generate /etc/adjtime
arch-chroot /mnt hwclock --systohc

# Set the hostname
echo "$HOSTNAME" > /mnt/etc/hostname

# Configure the hosts file (if your system has a permanent IP address, use that instead of 127.0.1.1)
echo "127.0.0.1 localhost"                          >> /mnt/etc/hosts
echo "::1       localhost"                          >> /mnt/etc/hosts
echo "127.0.1.1 $HOSTNAME.localdomain $HOSTNAME"    >> /mnt/etc/hosts

# Declare which locales we want to generate and generate them
sed -i '/#en_US.UTF-8 UTF-8/s/^#//g' /mnt/etc/locale.gen
sed -i '/#fr_FR.UTF-8 UTF-8/s/^#//g' /mnt/etc/locale.gen
sed -i '/#ja_JP.UTF-8 UTF-8/s/^#//g' /mnt/etc/locale.gen
arch-chroot /mnt locale-gen

# Set the system locale to the generated en_US.UTF-8
echo "LANG=en_US.UTF-8" > /mnt/etc/locale.conf

# Set the tty font to a larger one (same as the default setfont, but larger)
if [ "$HIDPI" == "YES" ]; then
  echo "FONT=latarcyrheb-sun32" > /mnt/etc/vconsole.conf
fi

# Install grub to the primary partition.
arch-chroot /mnt grub-install /dev/sda

# Prevent the GRUB window from showing at boot, ideal for single OS machines (undo with chroot and mkconfig)
sed -i '/GRUB_TIMEOUT/c\GRUB_TIMEOUT=0' /mnt/etc/default/grub

# Make the configuration file for grub.
arch-chroot /mnt grub-mkconfig -o /boot/grub/grub.cfg

# Change the shell of the root account to fish.
arch-chroot /mnt chsh -s /usr/bin/fish