[arch-general] arch linux repository

Hello... I am building a private repository (myrep) I put all the packages, I build using PKGBUILD and /var/abs/tree. and saved it on an internet server that can be acessed by using http. Is there a way to build the db and files in the repository, in a way pacman -Syu can update my archlinux??? or pacman just do not use them??? Thanks