Day 3 was about powering an escalator using batteries. Each battery bank is a string of digits, and the goal is to select specific digits to form the largest possible number. Part 1 was straightforward. Part 2… took some work.
The task: from each string of digits, pick exactly two to form the largest possible two-digit number. For example, from 811111111111119, you’d pick the 8 and 9 to get 89.
Day 2 brought a pattern-matching problem in the gift shop database. The task was to identify “invalid” product IDs - numbers that consist of a repeating sequence of digits.
The first part required finding numbers where a sequence repeats exactly twice: 11 (5 repeated twice), 1010 (10 repeated twice), 123123 (123 repeated twice), etc.
My approach was regex-first. I default to regex when pattern matching is involved because it’s expressive and, when it works, elegant. I always think back at:
Day 1 of Advent of Code 2025 is in the books. The puzzle involved a safe with a circular dial numbered 0-99, and the goal was to count how many times the dial landed on 0 after following a series of rotation instructions.
Part 1 was pretty straightforward. Given a starting position of 50 and a sequence of left (L) and right (R) rotations, I needed to count how many times the dial ended up pointing at 0 after each rotation.
I’ve been running Immich for about a year now, and it’s been one of the most reliable self-hosted services in my setup. For photo and video backups, it has just worked—smooth uploads, a clean timeline, and the peace of mind of keeping my media under my own control.
Recently, I started experimenting with the new beta timeline feature. That’s when I hit my first real bump: smaller uploads worked fine, but larger images and videos would consistently fail. Since I run Immich behind Traefik, my first thought was that it might be a proxy-related issue.
We’re deep under the ocean in our mini-submarine (again!), when the glow of a school of lanternfish catches your eye.
It turns out that these industrious lanternfish have built an elaborate network of warehouses to store food for their ever-growing population. Unfortunately, disaster has struck! A malfunctioning robot is wreaking havoc in one of their most critical warehouses, pushing boxes around with reckless abandon.
