All right, this is all I needed to know cited from that page: "XBase [...] is a general term for languages and tools derived from the Ashton Tate dBASE product

All right, this is all I needed to know cited from that page: "XBase [...] is a general term for languages and tools derived from the Ashton Tate dBASE product, popular in the 1980s and early 1990s. Clones include FoxPro, Quicksilver, dbXL, and a compiled dialect called Clipper (which spawned XbasePlusPlus, FlagShip, and Harbour)." "XBase originated as a table-oriented non-SQL language and tool vaguely influenced by relational theory and (mainly) cursor-oriented table navigation techniques from the 1960s. It was one of the first products that easily allowed small businesses access to database concepts such as ad-hoc queries, indexing, and data-driven CrudScreen RAD when microcomputers were just coming of age. [...]" "It allegedly has its roots in a legacy database product called RETRIEVE. The Pasadena Jet Propulsion Laboratory, famous for planetary probes, didn't want to pay licensing fees for RETRIEVE and so set out to create something similar. In a round-about way, it eventually wound up a commercial product for CPM microcomputers, and grew quite popular in the DOS world." There is an open source implementation at http://harbour-project.org/ http://harbour-project.org/ (-> http://harbour.github.io/ http://harbour.github.io/ ) whose latest version 3.0.0 was released on 2011-07-17, but the Github repo (imported from SourceForge) shows recent activity: https://github.com/harbour/core https://github.com/harbour/core