Hello Lispers!
Unfortunately the submitted tar is not full and I can't change the submission :(
UPD:
I created a guix pack, so I hope it will help to run the game.
You need to dowload birb-0.1-guix-pack.tar.gz from this release on my github repo,
unpack it with `tar -xf birb-0.1-guix-pack.tar.gz` and then run `bin/birb` executable.
Also you can build it from sources with Guix package manager. See README of the git project for more details https://github.com/kierros/birb