---
title: Advent of Code - Day 4
date: 2025-12-09T07:41:18.018Z
slug: 2025-12-09-advent-of-code-day-4
author: Thomas Wilson

---
Yesterday I finished Day 4 of the 2025 Advent of Code.  I've been keeping a _Reflections_ section of the `README.md` for each day - and while doing this challenge I kept a strong focus on modelling the problem rather than the solution or implementation.  

By that I mean: yes, it's all string and character manipulation - but aliasing data and operations behind classes and methods that make "sense" allowed me to think and reason about the work more clearly.

I think I'm at about a week of using Ruby nearly every day.  Which is pretty cool!

My full reflections at [the repo](https://github.com/thomaswilsonxyz/advent-of-code-2025/tree/main/day-4)
