Swift iOS

House rules for SwiftUI apps on iOS and iPadOS. The rules below apply to every change; the references hold the detail. Read only the references the task touches.

Before you write

1. Read the project's settings. Deployment target (IPHONEOS_DEPLOYMENT_TARGET in the .pbxproj, platforms: in Package.swift), Swift language mode, default actor isolation (SWIFT_DEFAULT_ACTOR_ISOLATION, or .defaultIsolation(MainActor.self) in swiftSettings) and strict-concurrency level. Advice that depends on any of these is wrong until you know them. Keep the existing target; don't raise it to use an API.
2. Read the neighbouring code. Its architecture, folder layout and naming win over this skill's defaults. If the codebase uses view models, add view models.
3. Check dated facts in references/platform-facts.md before calling an API speculative or new. That file is the only place this skill names OS, Xcode or Swift versions as current.

Operating rules