This work was done while the author was with the Department of Computer and Information Science, University of Pennsylvania. Ned Batchelder co-developed the original troff version of this program with the author, and was responsible for much of the overall design. For more detailed information on the original version of PostScript see Psfig – A Ditroff Preprocessor for PostScript Figures in the USENIX 87 proceedings, or Bringing troff up to speed in the July 1987 issue of Unix Review.
Greg Hager provided the initial pure-TEX implementation of psfig. J. Daniel Smith of Schlumberger CAD/CAM implemented the rotation feature and improved the file scanning routines, using certain code fragments from Tom Rokicki's dvips program.