(Постник Яковлев), is most famous as the architect and builder of Saint Basil's Cathedral
on Red Square
(built between 1555 and 1560). Origninally from Pskov, it is thought that he was nicknamed "Barma" (Барма) ("the mumbler"), although it might be that his full name was, in fact, Ivan Yakovlevich Barma; (Postnik means "Faster", a term used for several relgious figures, including Patriarch John IV of Constantinople); Barma might also be Yakovlev's assistant.
According to legend, Ivan the Terrible blinded Yakovlev so that he could never build anything so beautiful again. However, this is probably a myth, as Yakovlev, in cooperation with another master, Ivan ShirIai, designed the walls of the Kazan' Kremlin and the Cathedral of the Assumption in Kazan' in 1561 and 1562, just after the completion of St. Basil's. He also designed the northeast chapel of St. Basil's (where Basil himself, the popular Fool for Christ - yurodivy Vassily Blazhenny - is buried), in 1588, four years after Ivan's death.
According to several historians, Yakovlev also have designed churches in Staritsa, Murom, Sviazhsk, and perhaps Vladimir, although others contend that this was another architect with a similar name.