@Observable vs ObservableObject: What 1,000 Rows and a Redraw Counter Actually Showed Me
Day 13 of the 30-day iOS series. I built a redraw counter into BrewLog, put 1,000 rows in two identical lists side by side — one backed by @Observable, one by ObservableObject — and toggled a single favorite ten times. The row counts tied 10-10. The list counts didn't. Here's the real number, and exactly where it comes from.
ObservableObject → @Observable: The Migration Guide That Skips the Marketing (and the Autoclosure Gotcha Apple Forgot to Mention)
Day 11 of the 30-day iOS series. Apple's migration guide makes ObservableObject → @Observable look like a find-and-replace. It mostly is — except for one quiet behavioral change: @StateObject only ran your initializer once, and @State runs it on every render. Here's the multiple-init bug that causes, why it's worst in exactly the init you were proud of, and how to fix it with a test that turns 'no side effects in init' into a hard, green invariant.