Ask HN: Most interesting tech you built for just yourself?

There is also a telegram bot that can show me the latest camera image with vacant places highlighted.

The way it works is it generates an NFA for a rule. You can define sets of sounds, some of which can be multiple characters long, and also define distinctive features, which allows you to define how sounds change by adding or removing them, but also allows you to match groups of sounds based on combinations of distinctive features. It builds up these ad-hoc sets of sounds and produces a prefix tree, which it uses as a template to build the NFA. Finally, the NFA is converted to a DFA for performance. It takes a while (the console app is much faster than the browser demo), but the rules run many, many times, so they need to be fast. It's essentially a special purpose regex engine. I'm working on bug fixes and some enhancements for now, but it basically works.

Demo: https://marriola.github.io/transmute-demo

The Pi has a 5TB hard drive attached with perhaps 1000 videos or so. The app has a schedule and plays the videos according to the schedule. It starts up in the morning, plays tele-courses, moves on to old TV shows, an afternoon movie, after school shows begin around 3:00 PM, a comedy show around dinner time, an evening movie, some late-night content, then the Indian head and "We Will Resume Broadcasting Tomorrow Morning...."

It fills dead airtime by choosing randomly among (literally) thousands of YouTube short clips I have on the drive — or showing a title card indicating when the next show begins.

Partly it's a fantasy — to have my own "channel" with my own scheduled content — my fantasy station.

Partly it serves to put on content I would otherwise not be inclined to pull up, double click and watch. It adds the serendipitous element to TV watching that I miss before streaming. The movie "Charly" (1968) just came on last night and I am sure I have not seen it since I was a teenager — had to stop what I was doing and watch a few scenes I recall vividly.

Today's lineup here: https://engineersneedart.com/UHF/

(Since the schedule is in JSON format, it was easy enough to make a web front end to display today's schedule.)

It has improved pretty much all my skills. Fabrication, embedded software/controls, system integration, operations processes, research and learning and so on. So far it’s been my most challenging personal hobby project.