Solutions to the Protohackers challenges in Common Lisp.
I'm just learning, if you want well-written and commented code by an expert lisp hacker then read PAIP, not this.
You can download all dependencies and run any challenge with guix, for example:
guix shell -L extra-packages/ -m manifest.scm -- sbcl --load protohackers.asd --eval "(require :protohackers)" --load challenge0.lisp