Log onto metabo as root

sudo -u fsadmin -i
cd ~/git/FS-Mod/dist/arch
git pull
cp  PKGBUILD ~/aur/selfmade_stuff/fsmod/
cd ~/aur/selfmade_stuff/fsmod/
makepkg -C
exit
pacman -U /var/cache/aur/pkg/mediawiki-extension-<extension>-git-<version>-any.tar.pkg.tar.xz