i did some of the 2025 Advent of Code. i made it to day 8 before falling behind and not catching up again, but here are my 8 solutions:
AoC 2025please note that this is not my best or most readable code, just that which i hacked together in order to solve the problem of the day :)
here is an emacs extension i made some time ago. i use it to organize large photo dumps. i use it often, though it has some rough edges. it's called "photogal", which stands for photo Grouper And Labeler.
photogalit should run alright if you load it into a running emacs session and execute
M-x photogal
when i was working at new york public radio, we had a growing microservices-style architecture. it was largely supported by a long-running nginx reverse proxy which had picked up a lot of cruft over the years. i was charged with investigating some network routing issues. the whole thing was very difficult to debug, so i wrote a network test harness that allowed me to mock out all the microservices and carefully debug the nginx system under test.
unettestthis helped me to solve one of the most challenging debugging tasks of my career. ultimately, what was going on is that there was one javascript service which was generating error pages with 404 messages. those pages were bubbled up through other javascript libraries, one of which changed the HTTP status code to a success code 200 while still displaying the correct 404 error visually in the html, effectively lying about the state of things. this caused the nginx system to fail to identify 404 pages since the status code was being rudely, silently, and incorrectly modified between network handoffs.