 Minor alterations were made by the Caliphs Al @-@ Hakim bi @-@ Amr Allah in 1009 and Al @-@ Amir bi @-@ <unk> l @-@ Lah in 1125 . The Caliph al @-@ Hafiz ( 1129 – 1149 ) made significant further changes , adding a fourth arcade with keel arches , and a dome with elaborate carved stucco decorations in front of the transept . Since then , the mosque has been greatly enlarged and modified over the years . Of the original building little remains other than the arcades and some of the stucco decoration . 
