How PreferenceKey lets child views communicate information back up the view tree.

Borrowing, consuming, and why Swift's ownership model matters.

A practical mental model for protected state and cross-actor calls in Swift.

Structure SwiftData queries so the fetch logic stays predictable as your models evolve.

When Swift asks for Sendable and how to satisfy it cleanly.

Use traits deliberately so Swift Testing communicates intent instead of just decorating test code.