Kx Systems

KX is the vendor for the kdb+ time-series database and associated programming language Q, and developer of K from K1 to K4 (K4 remains accessible but its use is discouraged). Founded in 1993 by Arthur Whitney and Janet Lustgarten, it is fully owned by finance technology firm FD Technologies (formerly First Derivatives) since 2018.

Whitney began work on K after leaving Morgan Stanley where he had developed A+. Having developed the initial implementation K0, he joined with Lustgarten to commercialize the language, forming Kx Systems. Until 1998 the language was sold exclusively to UBS; when this contract expired, Kx began development of kdb+ and Q. First Derivatives first partnered with Kx to market its products in Europe beginning in 1999. It bought a 65% share in Kx in 2014, and the remaining shares in 2018, as Whitney and Lustgarten left to found Shakti.