@adamhaber I just finished day 16 - it was quite straightforward using multi-methods (used parse-body and eval-packet mms for part 1 and part 2 resp.). Actually the hardest was hand tracing the examples to understand the requirements.

interesting! can you share your solution?

Sure, here it is: https://github.com/KingCode/advent-of-code/blob/main/src/advent_of_code/_2021/day16/day16.clj