Gosamaru, who built Zakimi Castle, was considered an outstanding castle architect. The actual work gathered together many workers, from those involved in stone quarrying to transportation. Stones from Yamada Gusuku were transported by hand and used. The workers were assigned an area and used relays to ferry the stones to where tasks were allotted for masonry work.

The workers were not only from the Yutanza vicinity. Laborers were requisitioned from Kikai Island, Amami-Daito Island, Yoron Island, Okierabu Island, and the Kerama Islands as well.

Because of his prestige after the defeat of Hokuzan, Gosamaru's ruling power increased and on these islands it is related that people would say "Gosamaru is coming!" to crying children to make them quiet down. Perhaps it is the result of his gathering a labor force through authority and compulsion.