James Gordon Letwin (born July 2, 1952)[1] is an Americansoftware developer and one of the eleven earlyMicrosoft employees who posed for aniconic staff portrait taken in Albuquerque in 1978.[2]
Prior to joining Microsoft, he worked forHeathkit, portingColossal Cave Adventure to the computer[3] and working onHDOS andBenton Harbor BASIC.
Letwin's first project at Microsoft was writing aBASIC compiler. He is most noted for being the lead architect of theOS/2operating system on the Microsoft side, withEd Iacobucci being the lead architect fromIBM's side. Letwin contributed much of the design and code for several core components, including theHPFSfile system.[4]
Letwin left Microsoft in 1993 to "kick back" with his wife.[5] While at Microsoft he had become a millionaire, with a 2000Time article estimating his worth at around $20 million.[2] Since leaving Microsoft, Letwin has donated substantial amounts of money to environmental causes via theWilburforce Foundation, a charitable foundation created by him and his wife, Rose.[2]