YASGG is free software, released under the Beerware License

"THE BEER-WARE LICENSE" (Revision 42):

nomnomnom <nomnomnom [at] secure-mail.cc> wrote this software. As long as you
retain this notice you can do whatever you want with this stuff. If we meet
some day, and you think this stuff is worth it, you can buy me a beer in return.

And just in case, we also use the "No warranty" notice from MIT/X11 License

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.