Notes
Things I worked out the hard way and wrote down so the next person does not have to.
29 Aug 2026
The seat hold is the whole booking system
Three booking platforms in, the same problem shows up every time: reserving a finite resource when two people press the button at once.
6 min
15 Aug 2026
Accuracy is the wrong number for a phishing classifier
A model that always guesses safe scores well when most URLs are safe. What went wrong, and what I measured instead.
5 min
1 Aug 2026
Immutable ledgers, or why I stopped allowing edits
A corrected accounting entry made a report I had already sent out wrong. The fix was to stop allowing corrections.
4 min