In 1985, Arthur Whitney created the A programming language[2] to replace APL.[3] Other developers at Morgan Stanley extended it to A+, adding a graphical user interface (GUI) and other language features. The GUI A+ was released in 1988.

Arthur Whitney went on to create a proprietary array language named K. Like J, K omits the APL character set. It lacks some of the perceived complexities of A+, such as the existence of statements and two different modes of syntax.