It's 2025, and I've had a heck of a year, including not managing to write my weekly newsletter for a number of months now. One sign that things are slowly returning to normal is that I'm considering doing the Advent of Code.

Last year, I did it in Rust and I really enjoyed it. I've of course, not touched Rust all year, so I figured with a little over a week to go, whether I should try getting everything setup. As a challange, I thought I'd give a few of the infamous 2019 intcode puzzles a try.

These were a series of puzzles throughout the 2019 advent of code that required you to build an increasingly complex computer, starting with a couple of very simple opcodes and an in memory array, you could make a computer that executed intcode and see what the result was. I was doing it in Go in 2019, and I got utterly derailed about half way through because I got stuck understanding the blocking and non-blocking aspects of channels.

I'm going to give the first one or two a go from 2019 under the "intcode" module, and also I'm going to revisit the old aoc-runner library that was used before. I think I'd prefer to build each week with a library and a set of tests, and then a single main that runs each days solution on the respective days input. Reducing the external dependencies should make it much cleaner (I hope).

I'm keeping most of the utils that I wrote last year, some simple stuff like a coordinate and a grid is something that is very likely to come up.

Completed days

So far I've completed the following days:

• Advent of Code 2025

• Intcode Prep day 5 - Input and Output

• Intcode Prep day 1 - Lets get started

• Day 1 - Secret Entrance

• Day 2 - Repeating digits in really big numbers

• Day 3 - Finding the biggest numbers

Cheers