ShrinkIt

.SHK (regular NuFX archives), .SDK (NuFX disk images)

Initial release1987?Latest release

1.0.6 (GS), 3.4 (Apple II)
GS: 30 April 1992; 32 years ago (1992-04-30), A2: 24 January 1991; 33 years ago (1991-01-24)

Type of formatData compressionExtended from.BNY (Binary II envelope) .BQY (squeezed file in Binary II envelope) .BXY (NuFX in Binary II envelope)Extended to.SDK NuFX disk image

A NuFX archive is an archive file format that supports lossless data compression. It is usually given the file extension SHK; SDK may also be used to specify that the archive describes the entire contents of a disk.

History

Andy E. Nicholas designed the format as an improved replacement for the Binary II (.BNY) format, adding compression. He introduced it alongside a pkzip-like program called ShrinkIt for Apple II systems, which he later migrated to the Apple IIGS as GS-Shrinkit.

The specification was republished by Apple in its File Type Notes.^[1]