To speed up the build process. Here's a few simple steps on how to create a local mirror for maximum speed.

Prerequisites

• A local web-server with web-root @ /srv/http/

Set up mirror

The following steps can be constructed into a mirror.sh script. But the essentials are:

rm -rf /tmp/pacdb
mkdir -p /tmp/pacdb
sudo mkdir -p /srv/http/local_repo/os/x86_64
cd /srv/http/local_repo
sudo pacman --dbpath /tmp/pacdb -Syu -w --root /srv/http/local_repo --cachedir /srv/http/local_repo/os/x86_64 base base-devel linux linux-firmware btrfs-progs efibootmgr nano wpa_supplicant dialog nano lollypop gstreamer gst-plugins-good gnome-keyring nemo gpicview-gtk3 chromium awesome xorg-server xorg-xrandr xorg-twm xorg-xinit xterm feh slock xscreensaver terminus-font-otb gnu-free-fonts ttf-liberation xsel qemu ovmf openssh sshfs git htop pkgfile scrot dhclient wget smbclient cifs-utils libu2f-host pulseaudio pulseaudio-alsa pavucontrol python git python-psutil python-systemd python-pygeoip geoip-database syslinux haveged intel-ucode amd-ucode memtest86+ mkinitcpio-nfs-utils nbd zsh efitools arch-install-scripts b43-fwcutter broadcom-wl btrfs-progs clonezilla crda darkhttpd ddrescue dhclient dhcpcd dialog diffutils dmraid dnsmasq dnsutils dosfstools elinks ethtool exfat-utils f2fs-tools fsarchiver gnu-netcat gpm gptfdisk grml-zsh-config grub hdparm ipw2100-fw ipw2200-fw irssi iwd jfsutils lftp linux-atm linux-firmware lsscsi lvm2 man-db man-pages mc mdadm mtools nano ndisc6 netctl nfs-utils nilfs-utils nmap ntfs-3g ntp openconnect openssh openvpn partclone parted partimage ppp pptpclient refind-efi reiserfsprogs rp-pppoe rsync sdparm sg3_utils smartmontools sudo tcpdump testdisk usb_modeswitch usbutils vi vim-minimal vpnc wget wireless-regdb wireless_tools wpa_supplicant wvdial xfsprogs xl2tpd git python python-psutil python-systemd python-pygeoip geoip-database
sudo repo-add /srv/http/local_repo/os/x86_64/local_repo.db.tar.gz" "/srv/http/local_repo/os/x86_64/{*.pkg.tar.xz,*.pkg.tar.zst}"

As of 2020-03-14, these are the packages needed to:

• Create a archiso
• pacstrap essential packages
• Run archinstall and archinstall_gui

Using local mirror

To use this mirror, and only this mirror in test purposes for archinstall_gui, stripping down both the local and live-iso pacman.conf is recommended to avoid fuzz.

Edit and comment out any existing mirror-definitions in /etc/pacman.conf such as, core, extra, community and multilib. And add the following entry:

[local_repo]
Server = http://1.2.3.4/$repo/os/$arch
SigLevel = Optional TrustAll

Then, do the same to the pacman.conf of archiso, as it will be copied into the live environment and used during the build process.

Final note

This should ensure that you get maximum speed when locally building packages, as well as speeding up the build process of the iso and archinstall install steps.