I gotta say, that's pretty damn cool. It reminds me that I've been meaning to take up Common Lisp for, like, forever. But finding time to invest in learning the language / ecosystem is the perpetual challenge. :-(
Just do AoC in CL; start at the first year and do 1 per day. When reaching the following year (first day puzzles are much easier than the last one you did), add visualisations etc. When you reach AoC ‘24, you’ll be flying.
