ICFPC is an annual programming contest with a long history. Each year, individuals and teams of unlimited size compete to solve a single problem in 72 hours, with no constraints on the technologies they can use. In addition to the full leaderboard, the contest has Lightning Division – a separate leaderboard for the submissions made in the first 24 hours.The nature of the problem can’t be predicted in advance. Each year the contest has a new group of organizers (usually it’s the computer science department of this or that university; sometimes it’s organized by firms). The organizers try to play off the past contest themes but also to add something completely new.In 2014, the problem was to write an AI that plays the game of Pacman, both for Pacman and for ghosts. The twist was that Pacman had to run on the fantasy LISP machine specified in the problem description. And the AI for ghosts ran on the fantasy 8-bit microprocessors. It was not enough to write the AI, we had to implement two compilers as well.In 2020, the problem statement didn’t have any words in any of the human languages. It was presented as a sequence of messages from space, where aliens show their notation for arithmetic, then for boolean algebra, then for combinatorial calculus, then describe the communication protocol, and finally give a program that, in human terms, is a thin client for the galactic network. The participants deciphered the messages, implemented an emulator to run this “browser”, and discovered, well, spoilers.