emilkowal-animations-swift
Installation
SKILL.md
SwiftUI & AppKit Animation Best Practices
Comprehensive animation guide for Apple platform interfaces, adapted from Emil Kowalski's web animation principles and Framer Motion best practices. Contains 86 rules across 10 categories targeting iOS 17+, prioritized by impact.
Review Format (Required)
When reviewing UI animation code, you MUST use a markdown table with Before/After/Why columns. Do NOT use a list with "Before:" and "After:" on separate lines. Always output an actual markdown table like this:
| Before | After | Why |
|---|---|---|
.animation(.default) |
.animation(.easeOut(duration: 0.2)) |
Specify explicit easing; avoid default |
scaleEffect(0) |
scaleEffect(0.95) with .opacity(0) |
Nothing in the real world appears from nothing |
.easeIn on dropdown |
.easeOut(duration: 0.2) |
easeIn feels sluggish; easeOut gives instant feedback |
| No press feedback on button | scaleEffect(isPressed ? 0.97 : 1.0) |
Buttons must feel responsive to press |
.scaleEffect(anchor: .center) on popover |
.scaleEffect(anchor: .top) matching trigger |
Popovers should scale from their trigger, not center |
One row per issue found. The "Why" column briefly explains the reasoning.