This was my tenth(!) year building 25 days of puzzles for #AdventOfCode. You can solve them all for free! Most people write code to solve them, but you can solve them however you like. I hope they help people become better programmers. 🌟

The first puzzle comes out in two hours: https://adventofcode.com/

Advent of Code 2025

@ericwastl Thank you so much for all the effort you put into AoC! Its an amazing project and the highlight of every year's december <3
@ericwastl Thank you for all the effort you put in those problems, the website and the event.
@ericwastl I never participated, but I know people that have. Has there ever been a chemistry themed one? Is that still available?
@egonw There have been a few chemistry-themed puzzles, I think; all puzzles are still available.

@ericwastl The first problem can be solved with a spreadsheet program of your choice 🙂

Part 2 needs a more powerful language.

#AdventOfCode

@gunchleoc
Day 1 part 2 can also be solved with just a spreadsheet 😉
@ericwastl
@incredobler @ericwastl Probably. I just didn't feel like learning a new programming language or inserting tons of blank cells for aligning stuff
@ericwastl so grateful, it's always fun and a terrific challenge / learning opportunity :-)
@ericwastl This is my first year, and so far so good. Thanks very much for putting together such a fun project!
@ericwastl is base16 font on the page?

@ericwastl thank you

I do wish there was a more concise version of the problems

@juhp Just read the last sentence, then scroll up to get any term definitions you need. Skip the examples until you need them.
@ericwastl Thank you - feeling some déjà vu - okay I try to remember that 👍🏻
@ericwastl Hi, fancy seeing you here! Thank you for taking care of my Decembers for the past 5 years :D

I probably won't become a much better programmer but I'll have fun doing it.
@ericwastl Congratulations. I enjoyed solving some last year. I did one with a small spreadsheet. I also liked how some puzzles were brute-forceable, but the second part wasn’t and forced you to approach it differently (the planting manual for example.)