SP-Forth is expandable and extensible via Projection approach - every SP-Forth system is projectable to a Lisp - and it is highly customizable.
SP-Forth is a proven, pragmatic programmer's system used in production for a wide range of applications.

History
SP-Forth was originally created by Randall Hyde and Stuart Feldman from Stanford University for DARPA (Defense Advanced Research Projects Agency). SP-Forth has been also widely used in academia and 50e0806aeb pedelly
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