Bespoke software is cheap now

The best thing on Hacker News last week was a Show HN from someone who bought an abandoned eight-lane bowling center in a small Midwestern town and found that replacing its 2008 scoring system would cost somewhere between $80,000 and $120,000. Most of what that equipment does, they pointed out, is decide when to fire a relay on a machine that’s largely mechanical. So they built their own out of ESP32 boards, a Raspberry Pi as the lane computer and a wireless mesh with a wired RS485 fallback, for about $200 per pair of lanes.

The post doesn’t say much about AI. The comments do. Several people said Claude had written most of the firmware on their recent ESP32 projects, and one said the LCD driver alone used to take them a week. What’s new is that one person with a day job looked at the quote and decided to write it, and that’s now a reasonable decision rather than a heroic one.

My weekend

I did a much smaller version on Saturday. My Obsidian vault has had numbered folders for years, but not much else holding it together. I sat down with Claude Code and turned it into something closer to a system: a required type field on every note, different fields for projects and ideas, about ten saved views that pull out what’s active and what’s stalled, and four small skills so the agent follows the conventions next time without me re-explaining them. Capture to the inbox, give me a status, run the weekly review, tidy up.

No app would know that I want projects and ideas kept apart, or that my meetings folder is going away because it’s been empty since I moved the work notes out last year. And I wouldn’t have written it by hand, because it’s a weekend of fiddly YAML and I’d have given up the first time a view returned zero rows for no visible reason. (One did, and I noticed a day later. A filter at the top of the file is combined with each view’s own filter, so one view ended up asking for notes that were two types at once, without any warning. The agent found why.)

The Monday before, an agent finally set up the small VPS I’d been meaning to get since January, as a dev box reachable only over my tailnet. That was an evening of me approving things and reading what it did. In 2020 it would have been my weekend, and I’d probably have got the firewall wrong.

What doesn’t get cheaper

Owning it. The bowling system has to work on a full Saturday night while the person who wrote it is behind the bar, and when a board dies, nobody else knows how it works.

My vault is lower stakes and the same shape. I’m now the only maintainer of a small piece of software that runs my notes, and the first Obsidian update that changes how those views behave is my evening. I’ve cleaned up after a vendor API that vanished in 30 days, and I’ve cleaned up after internal tools whose only maintainer left, and I’m not sure which was worse.

At work the rule hasn’t moved: build it if it’s ours and we’ll keep caring about it, buy it if someone else will care about it more. What’s moved is how small the first kind can be. A tool for twelve people is worth building now, and so is one for an audience of one, and I have a lot more of those than I did a year ago.