Zipzop is a zip recompression program, that uses libzopfli to re/compress deflate streams. It uses iterations like g/zip compression levels, but from 1 to infinity. It originated from Komiya Atsushi's zipzop. Licence and original README (in Japanese) is inherited from original.
Usage: $ zipzop <iterations> <in_file> <out_file>
In test directory there are simple sef tests.