Version-sensitive. Every API name, SDK gate and browser-support claim below was verified on 2026-09-08 against primary sources. What against, and when, is in _jutsu/VERSIONS.md. If that date is old, re-verify before acting on a version number.

SwiftUI Motion

SwiftUI animation core. Loaded for any SwiftUI project (iOS, macOS, multi-target Apple). Concise rules here. Deep-dive in references/. Pair with ../motion-principles/SKILL.md (foundation) and ../mobile-principles/SKILL.md (touch UX).

Animation API decision tree