src/data/license.txt

   1 This demonstration project, aside from the Yukkuri Games logo, is
   2 released into the public domain.
   3
   4 The person who associated a work with this deed has dedicated the work
   5 to the public domain by waiving all of his or her rights to the work
   6 worldwide under copyright law, including all related and neighboring
   7 rights, to the extent allowed by law.
   8
   9 You can copy, modify, distribute and perform the work, even for
  10 commercial purposes, all without asking permission.
  11
  12 See https://creativecommons.org/publicdomain/zero/1.0/ for details.
  13
  14 The source code under src/yuu remains under the terms of the GNU GPL
  15 versions 2 or later, unless specified otherwise in the files.