It is based on another tool I have written, a2sketch[0]: that uses asciitosvg (still the php-variant[1]), generates a svg and feeds that into rough.js[2] (converts svg in sketchy svg)

[0]: https://github.com/arnehilmann/a2sketch

[1]: https://github.com/dhobsd/asciitosvg

[2]: https://github.com/pshihn/rough