Blog
Engineering notes from building things.
Write-ups of problems worth writing up — undocumented platform behavior, hardware that talks back, geometry that looks fine and won't print, and bugs whose real cause was three layers away from the symptom. RSS.
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Your tvOS Top Shelf tile is cached, and reinstalling won't clear it
The tile drew a placeholder for hours after the code was correct again. The Home screen caches the rendered tile, dedupes incoming content against it, and that cache survives uninstalling the app — only a reboot cleared it. Plus what actually works for getting logs out of a tvOS extension, and what an extension can and can't do with an App Group.
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Why your HealthKit widget shows zero every morning
The widget was wrong every morning and right the moment I opened the app — but its timestamp was fresh, so it wasn't stale, it was freshly wrong. HealthKit's store is encrypted while the phone is locked, and a query that fails for that reason is indistinguishable from a day with no data unless you read the error.