The AST package includes KornShell, nmake, and Unix programming libraries such as vmalloc and sfio. The software was created over more than 15 years in the Advanced Software Technology dept. of AT&T Labs Research (formerly in Bell Labs, Murray Hill). It is aimed at supporting the creation and maintenance of scalable, efficient software under Unix. The AST environment was also ported to Windows NT in Dave Korn's UWIN system.