| name | uniwind |
| description | Uniwind — Tailwind CSS v4 styling for React Native. Use when adding, building, or styling components in a React Native project that uses Tailwind with className. Triggers on: className on RN components, Tailwind classes in RN, global.css with @import 'uniwind', withUniwindConfig, withUniwind, metro.config.js with Uniwind, useResolveClassNames, useCSSVariable, getCSSVariable, useUniwind, dark:/light: theming, platform selectors (ios:/android:/native:/web:/tv:), data-[prop=value], responsive breakpoints (sm:/md:/lg:), important utilities (bg-red-500!), tailwind-variants, tv() variants, ScopedTheme, Uniwind.setTheme, Uniwind.updateCSSVariables, @theme, @utility, @variant, CSS variables in RN, colorClassName, tintColorClassName, contentContainerClassName, default styles, default RN component styles, Uniwind Pro (animations, transitions, shadow tree, native insets), safe area utilities, gradients, hairlineWidth(), fontScale(), pixelRatio(), light-dark(), OKLCH, cn, tailwind-merge, HeroUI Native, react-native-reusables, Gluestack. Does NOT handle migration — use migrate-nativewind-to-uniwind skill.
|
Uniwind — Complete Reference
Uniwind 1.6.0+ / Tailwind CSS v4 / React Native 0.81+ / Expo SDK 54+
If user has lower version, recommend updating to 1.6.0+ for best experience.
Uniwind brings Tailwind CSS v4 to React Native. All core React Native components support the className prop out of the box. Styles are compiled at build time — no runtime overhead.
Critical Rules
- Tailwind v4 only — Use
@import 'tailwindcss' not @tailwind base. Tailwind v3 is not supported.
- Never construct classNames dynamically — Tailwind scans at build time.
bg-${color}-500 will NOT work. Use complete string literals, mapping objects, or ternaries.
- Never use
cssInterop or remapProps — Those are NativeWind APIs. Uniwind does not override global components.
- No
tailwind.config.js — All config goes in global.css via @theme and @layer theme.
- No ThemeProvider required — Use
Uniwind.setTheme() directly.
withUniwindConfig must be the outermost Metro config wrapper.
- NEVER wrap
react-native or react-native-reanimated components with withUniwind — View, Text, Pressable, Image, TextInput, ScrollView, FlatList, Switch, Modal, Animated.View, Animated.Text, etc. already have full className support built in. Wrapping them with withUniwind will break behavior. Only use withUniwind for third-party components (e.g., expo-image, expo-blur, moti).
- Font families: single font only — React Native doesn't support fallbacks. Use
--font-sans: 'Roboto-Regular' not 'Roboto', sans-serif.
- All theme variants must define the same set of CSS variables — If
light defines --color-primary, then dark and every custom theme must too. Mismatched variables cause runtime errors.
accent- prefix is REQUIRED for non-style color props — This is crucial. Props like color (Button, ActivityIndicator), tintColor (Image), thumbColor (Switch), placeholderTextColor (TextInput) are NOT part of the style object. You MUST use the corresponding {propName}ClassName prop with accent- prefixed classes. Example: <ActivityIndicator colorClassName="accent-blue-500" /> NOT <ActivityIndicator className="text-blue-500" />. Regular Tailwind color classes (like text-blue-500) only work on className (which maps to style). For non-style color props, always use accent-.
- rem default is 16px — NativeWind used 14px. Set
polyfills: { rem: 14 } in metro config if migrating.
cssEntryFile must be a relative path string — Use './global.css' not path.resolve(__dirname, 'global.css').
- Deduplicate with
cn() when mixing custom CSS classes and Tailwind — Uniwind does NOT auto-deduplicate. If a custom CSS class (.card { padding: 16px }) and a Tailwind utility (p-6) set the same property, both apply with unpredictable results. Always wrap with cn('card', 'p-6') when there's overlap.
- Important utilities are supported — Tailwind important modifier works in classNames with
! at the end: bg-red-500!, active:bg-red-500!, ios:pt-12!. Leading !bg-red-500 syntax is deprecated. Important utilities override non-important utilities for the same style property, but inline style still overrides className.
Setup
Installation
bun install uniwind tailwindcss
Requires Tailwind CSS v4+.
global.css
Create a CSS entry file:
@import 'tailwindcss';
@import 'uniwind';
Import in your App component (e.g., App.tsx or app/_layout.tsx), NOT in index.ts/index.js — importing there breaks hot reload:
import './global.css';
The directory containing global.css is the app root — Tailwind scans for classNames starting from this directory.
Metro Configuration
const { getDefaultConfig } = require('expo/metro-config');
const { withUniwindConfig } = require('uniwind/metro');
const config = getDefaultConfig(__dirname);
module.exports = withUniwindConfig(config, {
cssEntryFile: './global.css',
polyfills: { rem: 16 },
extraThemes: ['ocean', 'sunset'],
dtsFile: './uniwind-types.d.ts',
debug: true,
isTV: false,
});
For most flows, keep defaults, only provide cssEntryFile.
Wrapper order — Uniwind must wrap everything else:
module.exports = withUniwindConfig(withOtherConfig(config, opts), { cssEntryFile: './global.css' });
module.exports = withOtherConfig(withUniwindConfig(config, { cssEntryFile: './global.css' }), opts);
Vite Configuration (v1.2.0+)
If user has storybook setup, add extra vite config:
import tailwindcss from '@tailwindcss/vite';
import { uniwind } from 'uniwind/vite';
import { defineConfig } from 'vite';
export default defineConfig({
plugins: [
tailwindcss(),
uniwind({
cssEntryFile: './src/global.css',
dtsFile: './src/uniwind-types.d.ts',
}),
],
});
TypeScript
Uniwind auto-generates a .d.ts file (default: ./uniwind-types.d.ts) after running Metro. Place it in src/ or app/ for auto-inclusion, or add to tsconfig.json:
{ "include": ["./uniwind-types.d.ts"] }
If user has some typescript errors related to classNames, just run metro server to build the d.ts file.
Expo Router Placement
project/
├── app/_layout.tsx ← import '../global.css' here
├── components/
├── global.css ← project root (best location)
└── metro.config.js ← cssEntryFile: './global.css'
If global.css is in app/ dir, add @source for sibling directories:
@import 'tailwindcss';
@import 'uniwind';
@source '../components';
Tailwind IntelliSense (VS Code / Cursor / Windsurf)
{
"tailwindCSS.classAttributes": [
"class", "className", "headerClassName",
"contentContainerClassName", "columnWrapperClassName",
"endFillColorClassName", "imageClassName", "tintColorClassName",
"ios_backgroundColorClassName", "thumbColorClassName",
"trackColorOnClassName", "trackColorOffClassName",
"selectionColorClassName", "cursorColorClassName",
"underlineColorAndroidClassName", "placeholderTextColorClassName",
"selectionHandleColorClassName", "colorsClassName",
"progressBackgroundColorClassName", "titleColorClassName",
"underlayColorClassName", "colorClassName",
"backdropColorClassName", "backgroundColorClassName",
"statusBarBackgroundColorClassName", "drawerBackgroundColorClassName",
"ListFooterComponentClassName", "ListHeaderComponentClassName"
],
"tailwindCSS.classFunctions": ["useResolveClassNames"]
}
Monorepo Support
Add @source directives in global.css for packages outside the CSS entry file's directory:
@import 'tailwindcss';
@import 'uniwind';
@source "../../packages/ui/src";
@source "../../packages/shared/src";
Also needed for node_modules packages that contain Uniwind classes (e.g., shared UI libraries).
Component Bindings
All core React Native components support className out of the box. Some have additional className props for sub-styles (like contentContainerClassName) and non-style color props (requiring accent- prefix).
Complete Reference
Legend: Props marked with ⚡ require the accent- prefix. Props in parentheses are platform-specific.
View
| Prop | Maps to | Prefix |
|---|
className | style | — |
Text
| Prop | Maps to | Prefix |
|---|
className | style | — |
selectionColorClassName | selectionColor | ⚡ accent- |
Pressable
| Prop | Maps to | Prefix |
|---|
className | style | — |
Supports active:, disabled:, focus: state selectors.
Image
| Prop | Maps to | Prefix |
|---|
className | style | — |
tintColorClassName | tintColor | ⚡ accent- |
TextInput
| Prop | Maps to | Prefix |
|---|
className | style | — |
cursorColorClassName | cursorColor | ⚡ accent- |
selectionColorClassName | selectionColor | ⚡ accent- |
placeholderTextColorClassName | placeholderTextColor | ⚡ accent- |
selectionHandleColorClassName | selectionHandleColor | ⚡ accent- |
underlineColorAndroidClassName | underlineColorAndroid (Android) | ⚡ accent- |
Supports focus:, active:, disabled: state selectors.
ScrollView
| Prop | Maps to | Prefix |
|---|
className | style | — |
contentContainerClassName | contentContainerStyle | — |
endFillColorClassName | endFillColor | ⚡ accent- |
FlatList
| Prop | Maps to | Prefix |
|---|
className | style | — |
contentContainerClassName | contentContainerStyle | — |
columnWrapperClassName | columnWrapperStyle | — |
ListHeaderComponentClassName | ListHeaderComponentStyle | — |
ListFooterComponentClassName | ListFooterComponentStyle | — |
endFillColorClassName | endFillColor | ⚡ accent- |
SectionList
| Prop | Maps to | Prefix |
|---|
className | style | — |
contentContainerClassName | contentContainerStyle | — |
ListHeaderComponentClassName | ListHeaderComponentStyle | — |
ListFooterComponentClassName | ListFooterComponentStyle | — |
endFillColorClassName | endFillColor | ⚡ accent- |
VirtualizedList
| Prop | Maps to | Prefix |
|---|
className | style | — |
contentContainerClassName | contentContainerStyle | — |
ListHeaderComponentClassName | ListHeaderComponentStyle | — |
ListFooterComponentClassName | ListFooterComponentStyle | — |
endFillColorClassName | endFillColor | ⚡ accent- |
Switch
| Prop | Maps to | Prefix |
|---|
thumbColorClassName | thumbColor | ⚡ accent- |
trackColorOnClassName | trackColor.true (on) | ⚡ accent- |
trackColorOffClassName | trackColor.false (off) | ⚡ accent- |
ios_backgroundColorClassName | ios_backgroundColor (iOS) | ⚡ accent- |
Note: Switch does NOT support className (className?: never in types). Use only the color-specific className props above. Supports disabled: state selector.
ActivityIndicator
| Prop | Maps to | Prefix |
|---|
className | style | — |
colorClassName | color | ⚡ accent- |
Button
| Prop | Maps to | Prefix |
|---|
colorClassName | color | ⚡ accent- |
Note: Button does not support className (no style prop on RN Button).
Modal
| Prop | Maps to | Prefix |
|---|
className | style | — |
backdropColorClassName | backdropColor | ⚡ accent- |
RefreshControl
| Prop | Maps to | Prefix |
|---|
className | style | — |
colorsClassName | colors (Android) | ⚡ accent- |
tintColorClassName | tintColor (iOS) | ⚡ accent- |
titleColorClassName | titleColor (iOS) | ⚡ accent- |
progressBackgroundColorClassName | progressBackgroundColor (Android) | ⚡ accent- |
ImageBackground
| Prop | Maps to | Prefix |
|---|
className | style | — |
imageClassName | imageStyle | — |
tintColorClassName | tintColor | ⚡ accent- |
SafeAreaView
| Prop | Maps to | Prefix |
|---|
className | style | — |
KeyboardAvoidingView
| Prop | Maps to | Prefix |
|---|
className | style | — |
contentContainerClassName | contentContainerStyle | — |
InputAccessoryView
| Prop | Maps to | Prefix |
|---|
className | style | — |
backgroundColorClassName | backgroundColor | ⚡ accent- |
TouchableHighlight
| Prop | Maps to | Prefix |
|---|
className | style | — |
underlayColorClassName | underlayColor | ⚡ accent- |
Supports active:, disabled: state selectors.
TouchableOpacity
| Prop | Maps to | Prefix |
|---|
className | style | — |
Supports active:, disabled: state selectors.
TouchableNativeFeedback
| Prop | Maps to | Prefix |
|---|
className | style | — |
Supports active:, disabled: state selectors.
TouchableWithoutFeedback
| Prop | Maps to | Prefix |
|---|
className | style | — |
Supports active:, disabled: state selectors.
Usage Examples
import { View, Text, Pressable, TextInput, ScrollView, FlatList, Switch, Image, ActivityIndicator, Modal, RefreshControl, Button } from 'react-native';
<View className="flex-1 bg-background p-4">
<Text className="text-foreground text-lg font-bold">Title</Text>
</View>
<Pressable className="bg-primary px-6 py-3 rounded-lg active:opacity-80 active:bg-primary/90 focus:ring-2">
<Text className="text-white text-center font-semibold">Press Me</Text>
</Pressable>
<TextInput
className="border border-border rounded-lg px-4 py-2 text-base text-foreground focus:border-primary"
placeholderTextColorClassName="accent-muted"
selectionColorClassName="accent-primary"
cursorColorClassName="accent-primary"
selectionHandleColorClassName="accent-primary"
underlineColorAndroidClassName="accent-transparent"
placeholder="Enter text..."
/>
<ScrollView className="flex-1" contentContainerClassName="p-4 gap-4">
{/* content */}
</ScrollView>
<FlatList
className="flex-1"
contentContainerClassName="p-4 gap-3"
columnWrapperClassName="gap-3"
ListHeaderComponentClassName="pb-4"
ListFooterComponentClassName="pt-4"
endFillColorClassName="accent-gray-100"
numColumns={2}
data={items}
renderItem={({ item }) => <ItemCard item={item} />}
/>
<Switch
thumbColorClassName="accent-white"
trackColorOnClassName="accent-primary"
trackColorOffClassName="accent-gray-300 dark:accent-gray-700"
ios_backgroundColorClassName="accent-gray-200"
/>
<Image className="w-6 h-6" tintColorClassName="accent-primary" source={icon} />
<ActivityIndicator className="m-4" colorClassName="accent-primary" size="large" />
<Button colorClassName="accent-primary" title="Submit" onPress={handleSubmit} />
<Modal className="flex-1" backdropColorClassName="accent-black/50">
{/* content */}
</Modal>
<RefreshControl
className="p-4"
tintColorClassName="accent-primary"
titleColorClassName="accent-gray-500"
colorsClassName="accent-primary"
progressBackgroundColorClassName="accent-white dark:accent-gray-800"
/>
<ImageBackground
className="flex-1 justify-center items-center"
imageClassName="opacity-50"
tintColorClassName="accent-blue-500"
source={bgImage}
>
<Text className="text-white text-2xl font-bold">Overlay</Text>
</ImageBackground>
<KeyboardAvoidingView
behavior="padding"
className="flex-1 bg-white"
contentContainerClassName="p-4 justify-end"
>
<TextInput className="border border-gray-300 rounded-lg p-3" placeholder="Type..." />
</KeyboardAvoidingView>
<InputAccessoryView
className="p-4 border-t border-gray-300"
backgroundColorClassName="accent-white dark:accent-gray-800"
>
<Button title="Done" onPress={dismissKeyboard} />
</InputAccessoryView>
<TouchableHighlight
className="bg-blue-500 px-6 py-3 rounded-lg"
underlayColorClassName="accent-blue-600 dark:accent-blue-700"
onPress={handlePress}
>
<Text className="text-white font-semibold">Press Me</Text>
</TouchableHighlight>
The accent- Prefix Pattern
React Native components have props like color, tintColor, thumbColor that are NOT part of the style object. To set these via Tailwind classes, use the accent- prefix with the corresponding {propName}ClassName prop:
<ActivityIndicator colorClassName="accent-blue-500 dark:accent-blue-400" />
<Button colorClassName="accent-primary" title="Submit" />
<Image className="w-6 h-6" tintColorClassName="accent-red-500" source={icon} />
<Switch thumbColorClassName="accent-white" trackColorOnClassName="accent-primary" />
<TextInput placeholderTextColorClassName="accent-gray-400 dark:accent-gray-600" />
CRITICAL Rule: className maps to the style prop — it handles layout, typography, backgrounds, borders, etc. But React Native has many color props that live OUTSIDE of style (like color, tintColor, thumbColor, placeholderTextColor). These require a separate {propName}ClassName prop with the accent- prefix. Without accent-, the class resolves to a style object — but these props expect a plain color string.
<ActivityIndicator className="text-blue-500" />
<ActivityIndicator colorClassName="accent-blue-500" />
<Image className="tint-blue-500" source={icon} />
<Image tintColorClassName="accent-blue-500" source={icon} />
Styling Third-Party Components
withUniwind (Recommended)
Wrap once at module level, use with className everywhere:
import { withUniwind } from 'uniwind';
import { Image as ExpoImage } from 'expo-image';
import { BlurView as RNBlurView } from 'expo-blur';
import { LinearGradient as RNLinearGradient } from 'expo-linear-gradient';
export const Image = withUniwind(ExpoImage);
export const BlurView = withUniwind(RNBlurView);
export const LinearGradient = withUniwind(RNLinearGradient);
withUniwind automatically maps:
style → className
{name}Style → {name}ClassName
{name}Color → {name}ColorClassName (with accent- prefix)
For custom prop mappings:
const StyledProgressBar = withUniwind(ProgressBar, {
width: {
fromClassName: 'widthClassName',
styleProperty: 'width',
},
});
Usage patterns:
- Used in one file only — define the wrapped component in that same file
- Used across multiple files — wrap once in a shared module (e.g.,
components/styled.ts) and re-export
import { withUniwind } from 'uniwind';
import { Image as ExpoImage } from 'expo-image';
export const Image = withUniwind(ExpoImage);
import { Image } from '@/components/styled';
NEVER call withUniwind on the same component in multiple files.
CRITICAL: Do NOT use withUniwind on components from react-native or react-native-reanimated. These already have built-in className support:
const StyledView = withUniwind(View);
const StyledText = withUniwind(Text);
const StyledAnimatedView = withUniwind(Animated.View);
const StyledExpoImage = withUniwind(ExpoImage);
const StyledBlurView = withUniwind(BlurView);
const StyledMotiView = withUniwind(MotiView);
useResolveClassNames
Converts Tailwind class strings to React Native style objects. Use for one-off cases or components that only accept style:
import { useResolveClassNames } from 'uniwind';
const headerStyle = useResolveClassNames('bg-primary p-4');
const cardStyle = useResolveClassNames('bg-card dark:bg-card rounded-lg shadow-sm');
<Stack.Navigator screenOptions={{ headerStyle, cardStyle }} />
Comparison
| Feature | withUniwind | useResolveClassNames |
|---|
| Setup | Once per component | Per usage |
| Performance | Optimized | Slightly slower |
| Best for | Reusable components | One-off, navigation config |
| Syntax | className="..." | style={...} |
Dynamic ClassNames
NEVER do this (Tailwind scans at build time)
<View className={`bg-${color}-500`} />
<Text className={`text-${size}`} />
Correct patterns
<View className={isActive ? 'bg-primary' : 'bg-muted'} />
const colorMap = {
primary: 'bg-blue-500 text-white',
danger: 'bg-red-500 text-white',
ghost: 'bg-transparent text-foreground',
};
<Pressable className={colorMap[variant]} />
<View className={[
'p-4 rounded-lg',
isActive && 'bg-primary',
isDisabled && 'opacity-50',
].filter(Boolean).join(' ')} />
tailwind-variants (tv)
For complex component styling with variants and compound variants:
import { tv } from 'tailwind-variants';
const button = tv({
base: 'font-semibold rounded-lg px-4 py-2 items-center justify-center',
variants: {
color: {
primary: 'bg-blue-500 text-white',
secondary: 'bg-gray-500 text-white',
danger: 'bg-red-500 text-white',
ghost: 'bg-transparent text-foreground border border-border',
},
size: {
sm: 'text-sm px-3 py-1.5',
md: 'text-base px-4 py-2',
lg: 'text-lg px-6 py-3',
},
disabled: {
true: 'opacity-50',
},
},
compoundVariants: [
{ color: 'primary', size: 'lg', class: 'bg-blue-600' },
],
defaultVariants: { color: 'primary', size: 'md' },
});
<Pressable className={button({ color: 'primary', size: 'lg' })}>
<Text className="text-white font-semibold">Click</Text>
</Pressable>
cn Utility — Class Deduplication
Uniwind does NOT auto-deduplicate conflicting classNames. This means if the same property appears in multiple classes, both will be applied and the result is unpredictable. This is especially critical when mixing custom CSS classes with Tailwind utilities.
Setup
npm install tailwind-merge clsx
import { type ClassValue, clsx } from 'clsx';
import { twMerge } from 'tailwind-merge';
export function cn(...inputs: ClassValue[]) {
return twMerge(clsx(inputs));
}
When cn Is Required
- Merging className props — component accepts external className that may conflict:
import { cn } from '@/lib/cn';
<View className={cn('p-4 bg-white', props.className)} />
<Text className={cn('text-base', isActive && 'text-primary', disabled && 'opacity-50')} />
- CRITICAL: Mixing custom CSS classes with Tailwind utilities — if your custom CSS class sets a property that a Tailwind utility also sets, you MUST use
cn() to deduplicate:
.card {
background-color: white;
border-radius: 12px;
padding: 16px;
}
<View className="card p-6" />
<View className={cn('card', 'p-6')} />
- tv() output combined with extra classes — tv already handles its own variants, but if you add more classes on top:
<Pressable className={cn(button({ color: 'primary' }), props.className)} />
When cn Is NOT Needed
- Static className with no conflicts:
<View className="flex-1 p-4 bg-white" />
- Single custom CSS class with no overlapping Tailwind:
<View className="card-shadow mt-4" /> (if card-shadow only sets box-shadow which no Tailwind class also sets)
Important Utilities and Style Specificity
Uniwind supports Tailwind's important modifier (!) for utilities that must override another utility for the same style property.
import { View, Pressable } from 'react-native';
<View className="bg-blue-500 bg-red-500!" />;
<Pressable className="bg-blue-500 active:bg-red-500!" />;
<View className="pt-4 ios:pt-12! android:pt-8!" />;
Priority rules:
- Important utility (
bg-red-500!) overrides non-important utility (bg-blue-500) for the same property.
- Important variants work normally:
active:bg-red-500!, ios:pt-12!, dark:text-white!.
- Inline
style always wins, even over important className utilities: <View className="bg-red-500!" style={{ backgroundColor: 'blue' }} /> renders blue.
- Use
! sparingly. For reusable components and consumer overrides, prefer cn() with tailwind-merge.
Theming
Quick Setup (dark: prefix)
Works immediately — no configuration needed:
<View className="bg-white dark:bg-gray-900">
<Text className="text-black dark:text-white">Themed</Text>
</View>
Best for small apps and prototyping. Does not scale to custom themes.
Scalable Setup (CSS Variables)
Define in global.css, use everywhere without dark: prefix:
@layer theme {
:root {
@variant light {
--color-background: #ffffff;
--color-foreground: #111827;
--color-foreground-secondary: #6b7280;
--color-card: #ffffff;
--color-border: #e5e7eb;
--color-muted: #9ca3af;
--color-primary: #3b82f6;
--color-danger: #ef4444;
--color-success: #10b981;
}
@variant dark {
--color-background: #000000;
--color-foreground: #ffffff;
--color-foreground-secondary: #9ca3af;
--color-card: #1f2937;
--color-border: #374151;
--color-muted: #6b7280;
--color-primary: #3b82f6;
--color-danger: #ef4444;
--color-success: #10b981;
}
}
}
<View className="bg-card border border-border p-4 rounded-lg">
<Text className="text-foreground text-lg font-bold">Title</Text>
<Text className="text-muted mt-2">Subtitle</Text>
</View>
Variable naming: --color-background → bg-background, text-background.
Prefer CSS variables over explicit dark: variants — they're cleaner, maintain easier, and work with custom themes automatically.
Custom Themes
Step 1 — Define in global.css:
@layer theme {
:root {
@variant light { }
@variant dark { }
@variant ocean {
--color-background: #0c4a6e;
--color-foreground: #e0f2fe;
--color-primary: #06b6d4;
--color-card: #0e7490;
--color-border: #155e75;
}
}
}
Step 2 — Register in metro.config.js (exclude light/dark — they're automatic):
module.exports = withUniwindConfig(config, {
cssEntryFile: './global.css',
extraThemes: ['ocean'],
});
Restart Metro after adding themes.
Step 3 — Use:
Uniwind.setTheme('ocean');
Theme API
import { Uniwind, useUniwind } from 'uniwind';
Uniwind.setTheme('dark');
Uniwind.setTheme('light');
Uniwind.setTheme('system');
Uniwind.setTheme('ocean');
Uniwind.currentTheme;
Uniwind.hasAdaptiveThemes;
const { theme, hasAdaptiveThemes } = useUniwind();
Uniwind.setTheme('light') / setTheme('dark') also calls Appearance.setColorScheme to sync native components (Alert, Modal, system dialogs).
By default Uniwind uses "system" theme - follows device color scheme. If user wants to override it, just
call Uniwind.setTheme with desired theme. It can be done above the React component to avoid theme switching at runtime.
Theme Switcher Example
import { View, Pressable, Text, ScrollView } from 'react-native';
import { Uniwind, useUniwind } from 'uniwind';
export const ThemeSwitcher = () => {
const { theme, hasAdaptiveThemes } = useUniwind();
const activeTheme = hasAdaptiveThemes ? 'system' : theme;
const themes = [
{ name: 'light', label: 'Light' },
{ name: 'dark', label: 'Dark' },
{ name: 'system', label: 'System' },
];
return (
<ScrollView horizontal showsHorizontalScrollIndicator={false}>
<View className="flex-row gap-2 p-4">
{themes.map((t) => (
<Pressable
key={t.name}
onPress={() => Uniwind.setTheme(t.name)}
className={`px-4 py-3 rounded-lg items-center ${
activeTheme === t.name ? 'bg-primary' : 'bg-card border border-border'
}`}
>
<Text className={`text-sm ${
activeTheme === t.name ? 'text-white' : 'text-foreground'
}`}>
{t.label}
</Text>
</Pressable>
))}
</View>
</ScrollView>
);
};
ScopedTheme
Apply a different theme to a subtree without changing the global theme:
import { ScopedTheme } from 'uniwind';
<View className="gap-3">
<PreviewCard />
<ScopedTheme theme="dark">
<PreviewCard /> {/* Renders with dark theme */}
</ScopedTheme>
<ScopedTheme theme="ocean">
<PreviewCard /> {/* Renders with ocean theme */}
</ScopedTheme>
</View>
- Nearest
ScopedTheme wins (nested scopes supported)
- Hooks (
useUniwind, useResolveClassNames, useCSSVariable) resolve against the nearest scoped theme
withUniwind-wrapped components inside the scope also resolve scoped theme values
- Custom themes require registration in
extraThemes
useCSSVariable
Access CSS variable values in JavaScript:
import { useCSSVariable } from 'uniwind';
const primaryColor = useCSSVariable('--color-primary');
const spacing = useCSSVariable('--spacing-4');
const [bg, fg] = useCSSVariable(['--color-background', '--color-foreground']) as [string, string]
Use for: animations, chart libraries, third-party component configs, calculations with design tokens.
It's required to cast the result of useCSSVariable as it can return: string | number | undefined.
Uniwind doesn't know if given variable exist and what type it is, so it returns union type.
getCSSVariable
Read CSS variable values outside of React (event handlers, async callbacks, utility modules, worklets). Available in Uniwind 1.6.4+.
import { Uniwind } from 'uniwind';
const primary = Uniwind.getCSSVariable('--color-primary');
const [bg, fg] = Uniwind.getCSSVariable(['--color-background', '--color-foreground']) as [string, string];
Same value rules as useCSSVariable (variable must be used in a className or declared in @theme static). Same return type: string | number | undefined. Cast as needed.
Not reactive — value is read once. For reactive values inside components use useCSSVariable. Use getCSSVariable for one-shot reads (onPress handlers, utility functions, native module configs).
Runtime CSS Variable Updates
Update theme variables at runtime (e.g., user-selected brand colors or API-driven themes):
Uniwind.updateCSSVariables('light', {
'--color-primary': '#ff6600',
'--color-background': '#fafafa',
});
Updates are theme-specific and take effect immediately.
@theme static
For JS-only values not used in classNames:
@theme static {
--chart-line-width: 2;
--chart-dot-radius: 4;
--animation-duration: 300;
}
Access via useCSSVariable('--chart-line-width'). Use for: chart configs, animation durations, native module values.
OKLCH Colors support
Perceptually uniform color format — wider gamut, consistent lightness:
@layer theme {
:root {
@variant light {
--color-primary: oklch(0.5 0.2 240);
--color-background: oklch(1 0 0);
}
@variant dark {
--color-primary: oklch(0.6 0.2 240);
--color-background: oklch(0.13 0.004 17.69);
}
}
}
Display P3 Colors support
Wide-gamut color format for devices that support the P3 color space (most modern iPhones and Macs). Uniwind parses color(display-p3 ...) values and converts them for native use:
@layer theme {
:root {
@variant light {
--color-primary: color(display-p3 0.2 0.4 1);
--color-accent: color(display-p3 1 0.3 0.3);
}
@variant dark {
--color-primary: color(display-p3 0.3 0.5 1);
--color-accent: color(display-p3 1 0.4 0.4);
}
}
}
Platform Selectors
Apply platform-specific styles directly in className:
<View className="ios:bg-red-500 android:bg-blue-500 web:bg-green-500" />
<View className="native:bg-blue-500 web:bg-gray-500" />
<View className="tv:p-8 android-tv:bg-black apple-tv:bg-gray-900" />
<View className="p-4 ios:pt-12 android:pt-6 web:pt-4" />
Platform variants in @layer theme for global values (use @variant, not @media):
@layer theme {
:root {
@variant ios { --font-sans: 'SF Pro Text'; }
@variant android { --font-sans: 'Roboto-Regular'; }
@variant web { --font-sans: 'Inter'; }
}
}
Prefer platform selectors over Platform.select() — cleaner syntax, no imports needed.
Data Selectors
Style based on prop values using data-[prop=value]:utility:
<Pressable
data-selected={isSelected}
className="border rounded px-3 py-2 data-[selected=true]:ring-2 data-[selected=true]:ring-primary"
/>
<View
data-state={isOpen ? 'open' : 'closed'}
className="p-4 data-[state=open]:bg-muted/50 data-[state=closed]:bg-transparent"
/>
<Pressable
data-selected={route.key === current}
className="px-4 py-2 rounded-md text-foreground/60
data-[selected=true]:bg-primary data-[selected=true]:text-white"
>
<Text>{route.title}</Text>
</Pressable>
<Pressable
data-checked={enabled}
className="h-6 w-10 rounded-full bg-muted data-[checked=true]:bg-primary"
>
<View className="h-5 w-5 rounded-full bg-background translate-x-0 data-[checked=true]:translate-x-4" />
</Pressable>
Rules:
- Only equality selectors supported (
data-[prop=value])
- No presence-only selectors (
data-[prop] — not supported)
- No
has-data-* parent selectors (not supported in React Native)
- Booleans match both boolean and string forms
Interactive States
<Pressable className="bg-primary active:bg-primary/80 active:opacity-90 active:scale-95">
<Text className="text-white">Press me</Text>
</Pressable>
<Pressable
disabled={isLoading}
className="bg-primary disabled:bg-gray-300 disabled:opacity-50"
>
<Text className="text-white disabled:text-gray-500">Submit</Text>
</Pressable>
<TextInput
className="border border-border rounded-lg px-4 py-2 focus:border-primary focus:ring-2 focus:ring-primary/20"
/>
<Pressable className="bg-card rounded-lg p-4 focus:ring-2 focus:ring-primary">
<Text className="text-foreground">Focusable</Text>
</Pressable>
Components with state support:
- Pressable:
active:, disabled:, focus:
- TextInput:
active:, disabled:, focus:
- Switch:
disabled:
- Text:
active:, disabled:
- TouchableOpacity / TouchableHighlight / TouchableNativeFeedback / TouchableWithoutFeedback:
active:, disabled:
Responsive Breakpoints
Mobile-first — unprefixed styles apply to all sizes, prefixed styles apply at that breakpoint and above:
| Prefix | Min Width | Typical Device |
|---|
| (none) | 0px | All (mobile) |
sm: | 640px | Large phones |
md: | 768px | Tablets |
lg: | 1024px | Landscape tablets |
xl: | 1280px | Desktops |
2xl: | 1536px | Large desktops |
<View className="p-4 sm:p-6 lg:p-8">
<Text className="text-base sm:text-lg lg:text-xl font-bold">Responsive</Text>
</View>
<View className="flex-row flex-wrap">
<View className="w-full sm:w-1/2 lg:w-1/3 p-2">
<View className="bg-card p-4 rounded"><Text>Item</Text></View>
</View>
</View>
<View className="hidden sm:flex flex-row gap-4">
<Text>Visible on tablet+</Text>
</View>
<View className="flex sm:hidden">
<Text>Mobile only</Text>
</View>
Custom breakpoints:
@theme {
--breakpoint-xs: 480px;
--breakpoint-tablet: 820px;
--breakpoint-3xl: 1920px;
}
Usage: xs:p-2 tablet:p-4 3xl:p-8
Design mobile-first — start with base styles (no prefix), enhance with breakpoints:
<View className="w-full sm:w-3/4 md:w-1/2 lg:w-1/3" />
<View className="w-full lg:w-1/2 md:w-3/4 sm:w-full" />
Safe Area Utilities
Padding
| Class | Description |
|---|
p-safe | All sides |
pt-safe / pb-safe / pl-safe / pr-safe | Individual sides |
px-safe / py-safe | Horizontal / vertical |
Margin
| Class | Description |
|---|
m-safe | All sides |
mt-safe / mb-safe / ml-safe / mr-safe | Individual sides |
mx-safe / my-safe | Horizontal / vertical |
Positioning
| Class | Description |
|---|
inset-safe | All sides |
top-safe / bottom-safe / left-safe / right-safe | Individual sides |
x-safe / y-safe | Horizontal / vertical inset |
Compound Variants
| Pattern | Behavior | Example |
|---|
{prop}-safe-or-{value} | Math.max(inset, value) — ensures minimum spacing | pt-safe-or-4 |
{prop}-safe-offset-{value} | inset + value — adds extra spacing on top of inset | pb-safe-offset-4 |
Setup
Uniwind Free (default) — requires react-native-safe-area-context to update insets.
Wrap your App component in SafeAreaProvider and SafeAreaListener and call Uniwind.updateInsets(insets) in the onChange callback:
import { SafeAreaProvider, SafeAreaListener } from 'react-native-safe-area-context';
import { Uniwind } from 'uniwind';
export default function App() {
return (
<SafeAreaProvider>
<SafeAreaListener
onChange={({ insets }) => {
Uniwind.updateInsets(insets);
}}
>
<View className="pt-safe px-safe">{/* content */}</View>
</SafeAreaListener>
</SafeAreaProvider>
);
}
Uniwind Pro — automatic, no setup needed. Insets injected from native layer.
CSS Functions
Uniwind provides CSS functions for device-aware and theme-aware styling. These can be used everywhere (custom CSS classes, @utility, etc.) — but NOT inside @theme {} (which only accepts static values). Use @utility to create reusable Tailwind-style utility classes:
hairlineWidth()
Returns the thinnest line width displayable on the device. Use for subtle borders and dividers.
@utility h-hairline { height: hairlineWidth(); }
@utility border-hairline { border-width: hairlineWidth(); }
@utility w-hairline { width: calc(hairlineWidth() * 10); }
<View className="h-hairline bg-gray-300" />
<View className="border-hairline border-gray-200 rounded-lg p-4" />
fontScale(multiplier?)
Multiplies a base value by the device's font scale accessibility setting. Ensures text respects user preferences for larger or smaller text.
fontScale() — uses multiplier 1 (device font scale × 1)
fontScale(0.9) — smaller scale
fontScale(1.2) — larger scale
@utility text-sm-scaled { font-size: fontScale(0.9); }
@utility text-base-scaled { font-size: fontScale(); }
@utility text-lg-scaled { font-size: fontScale(1.2); }
<Text className="text-sm-scaled text-gray-600">Small accessible text</Text>
<Text className="text-base-scaled">Regular accessible text</Text>
pixelRatio(multiplier?)
Multiplies a value by the device's pixel ratio. Creates pixel-perfect designs that scale across screen densities.
pixelRatio() — uses multiplier 1 (device pixel ratio × 1)
pixelRatio(2) — double the pixel ratio
@utility w-icon { width: pixelRatio(); }
@utility w-avatar { width: pixelRatio(2); }
<Image source={{ uri: 'avatar.png' }} className="w-avatar rounded-full" />
light-dark(lightValue, darkValue)
Returns different values based on the current theme mode. Automatically adapts when the theme changes — no manual switching logic needed.
- First parameter: value for light theme
- Second parameter: value for dark theme
@utility bg-adaptive { background-color: light-dark(#ffffff, #1f2937); }
@utility text-adaptive { color: light-dark(#111827, #f9fafb); }
@utility border-adaptive { border-color: light-dark(#e5e7eb, #374151); }
<View className="bg-adaptive border-adaptive border rounded-lg p-4">
<Text className="text-adaptive">Adapts to light/dark theme</Text>
</View>
Also works in custom CSS classes (not just @utility):
.adaptive-card {
background-color: light-dark(#ffffff, #1f2937);
color: light-dark(#111827, #f9fafb);
}
Custom CSS & Utilities
Custom CSS Classes
Uniwind supports custom CSS class names defined in global.css. They are compiled at build time — no runtime overhead. Use them when you need styles that are hard to express as Tailwind utilities (e.g., complex box-shadow, multi-property bundles).
.card-shadow {
background-color: white;
border-radius: 12px;
box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}
.adaptive-surface {
background-color: light-dark(#ffffff, #1f2937);
color: light-dark(#111827, #f9fafb);
}
.container {
flex: 1;
width: 100%;
max-width: 1200px;
}
Apply via className just like any Tailwind class:
<View className="card-shadow" />
Mixing Custom CSS with Tailwind
You can combine custom CSS classes with Tailwind utilities in a single className:
<View className="card-shadow p-4 m-2">
<Text className="adaptive-surface mb-2">{title}</Text>
<View className="container flex-row">{children}</View>
</View>
WARNING: If a custom CSS class and a Tailwind utility set the same property, you MUST use cn() to deduplicate. Without cn(), both values apply and the result is unpredictable:
<View className="card-shadow rounded-2xl" />
import { cn } from '@/lib/cn';
<View className={cn('card-shadow', 'rounded-2xl')} />
Rule of thumb: If your custom CSS class sets properties that might overlap with Tailwind utilities you'll also use, always wrap with cn(). See cn Utility section for full setup.
Guidelines for Custom CSS
- Keep selectors flat — no deep nesting or child selectors
- Prefer Tailwind utilities for simple, single-property styles
- Use custom classes for complex or multi-property bundles that would be verbose in className
- Use
light-dark() for theme-aware custom classes
- Custom classes are great for shared design tokens that don't fit Tailwind's naming (e.g.,
.card, .chip, .badge-dot)
Custom Utilities (@utility)
The @utility directive creates utility classes that work exactly like built-in Tailwind classes. Three main use cases:
1. Variable-driven utilities (runtime-injected values)
Create a utility whose value comes from a CSS variable injected at runtime via updateCSSVariables. Use @theme static to declare the variable so Uniwind tracks it even before it is updated:
@theme static {
--header-height: 0px;
}
@utility p-safe-header {
padding-top: var(--header-height);
}
Inject the real value at runtime (e.g., from react-navigation's layout event):
import { Uniwind } from 'uniwind'
Uniwind.updateCSSVariables(Uniwind.currentTheme, {
'--header-height': headerHeight,
})
<View className="p-safe-header flex-1" />
2. Brand-new utilities (no Tailwind equivalent)
For styles that have no built-in Tailwind class:
@utility h-hairline { height: hairlineWidth(); }
@utility text-scaled { font-size: fontScale(); }
@utility card-shadow {
box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}
Usage like any Tailwind class: <View className="h-hairline card-shadow" />
3. Overriding existing Tailwind utilities
Use @utility to completely replace what a built-in class does. Example: make border always use --color-primary:
@utility border {
border-width: 1px;
border-style: solid;
border-color: var(--color-primary);
}
@theme Directive
Customize Tailwind design tokens in global.css:
@theme {
--color-primary: #3b82f6;
--color-brand-500: #3b82f6;
--color-brand-900: #1e3a8a;
--font-sans: 'Roboto-Regular';
--font-sans-medium: 'Roboto-Medium';
--font-sans-bold: 'Roboto-Bold';
--font-mono: 'FiraCode-Regular';
--text-base: 15px;
--spacing-4: 16px;
--radius-lg: 12px;
--breakpoint-tablet: 820px;
}
Usage: bg-brand-500, text-brand-900, font-sans, font-mono, rounded-lg.
Fonts
React Native requires a single font per family — no fallbacks:
@theme {
--font-sans: 'Roboto-Regular';
--font-sans-bold: 'Roboto-Bold';
--font-mono: 'FiraCode-Regular';
}
Font name must exactly match the font file name (without extension).
Expo: Configure fonts in app.json with the expo-font plugin, then reference in CSS.
Bare RN: Use react-native-asset to link fonts, same CSS config.
Platform-specific fonts (use @variant, not @media):
@layer theme {
:root {
@variant ios { --font-sans: 'SF Pro Text'; }
@variant android { --font-sans: 'Roboto-Regular'; }
@variant web { --font-sans: 'system-ui'; }
}
}
Gradients
Built-in support — no extra dependencies:
<View className="bg-gradient-to-r from-red-500 via-yellow-500 to-green-500 p-4 rounded-lg">
<Text className="text-white font-bold">Gradient</Text>
</View>
For expo-linear-gradient, you can wrap it with withUniwind for className-based layout and styling (padding, border-radius, flex, etc.), but the colors prop is an array that cannot be resolved via className — it must be provided explicitly. Use useCSSVariable to get theme-aware colors:
import { useCSSVariable } from 'uniwind';
import { withUniwind } from 'uniwind';
import { LinearGradient as RNLinearGradient } from 'expo-linear-gradient';
const LinearGradient = withUniwind(RNLinearGradient);
function GradientCard() {
const primary = useCSSVariable('--color-primary');
const secondary = useCSSVariable('--color-secondary');
if (!primary || !secondary) {
return null;
}
return (
<LinearGradient
className="flex-1 rounded-2xl p-6"
colors={[primary as string, secondary as string]}
>
<Text className="text-white font-bold">Themed gradient</Text>
</LinearGradient>
);
}
Alternatively, export a wrapped component from a shared module for reuse:
import { withUniwind } from 'uniwind';
import { LinearGradient as RNLinearGradient } from 'expo-linear-gradient';
export const LinearGradient = withUniwind(RNLinearGradient);
import { LinearGradient } from '@/components/styled';
<LinearGradient className="rounded-xl p-4" colors={['#ff6b6b', '#4ecdc4']}>
<Text className="text-white">Static gradient</Text>
</LinearGradient>
React Navigation Integration
Use useResolveClassNames for screen options that only accept style objects:
import { useResolveClassNames } from 'uniwind';
function Layout() {
const headerStyle = useResolveClassNames('bg-background');
const headerTitleStyle = useResolveClassNames('text-foreground font-bold');
return (
<Stack.Navigator
screenOptions={{
headerStyle,
headerTitleStyle,
}}
/>
);
}
Keep React Navigation's <ThemeProvider> if already in use — it manages navigation-specific theming.
UI Kit Compatibility
Use semantic color tokens (bg-primary, text-foreground) for theme consistency across UI kits.
Supported vs Unsupported Classes
React Native uses the Yoga layout engine. Key differences from web CSS:
- No CSS cascade/inheritance — styles don't inherit from parents
- Flexbox by default — all views use flexbox with
flexDirection: 'column'
- Limited CSS properties — no floats, grid, pseudo-elements
Built-in Extra Utilities
Uniwind provides additional utility classes for React Native features not covered by standard Tailwind:
| Class | Effect |
|---|
border-continuous | Sets borderCurve: 'continuous' — smooth, superellipse corners (iOS) |
border-circular | Sets borderCurve: 'circular' — standard circular corners (iOS default) |
<View className="rounded-2xl border-continuous bg-card p-4">
<Text className="text-foreground">Smooth corners</Text>
</View>
Supported (all standard Tailwind)
Layout, spacing, sizing, typography, colors, borders, effects, flexbox, positioning, transforms, interactive states.
Unsupported (web-specific, silently ignored)
hover: visited: — use Pressable active: instead
before: after: placeholder: — pseudo-elements
float-* clear-* columns-*
print: screen:
break-before-* break-after-* break-inside-*
Uniwind Pro
Paid upgrade with 100% API compatibility. Built on a 2nd-generation C++ engine for apps that demand the best performance. Graduated pricing (billed annually): $99/seat (1-3), $49 (4-6), $29 (7-15), $1 (16+). Pricing and licensing: https://uniwind.dev/pricing
Pricing & Licensing
- Graduated per-seat pricing (billed annually, VAT excluded unless applicable): $99 for seats 1-3, $49 for 4-6, $29 for 7-15, $1 for 16+
- Individual License: Personal Pro license per engineer
- Team License: Single key management — add or remove members instantly
- CI/CD License: Full support for automated and headless build environments
- Enterprise: Custom plans available (contact support@uniwind.dev)
- Priority Support: Critical issues resolved with priority response times
Overview
- C++ style engine: Forged on the 2nd-gen Unistyles C++ engine. Injects styles directly into the ShadowTree without triggering React re-renders — a direct, optimized highway between classNames and the native layer
- Performance: Benchmarked at ~55ms (vs StyleSheet 49ms, traditional Uniwind 81ms, NativeWind 197ms) — near-native speed
- 55+ className props update without re-renders across 20 components (all component bindings listed above)
- Reanimated animations:
animate-* and transition-* via className (Reanimated v4)
- Native insets & runtime values: Automatic safe area injection, device rotation, and font size updates — no
SafeAreaListener setup needed
- Theme transitions: Native animated transitions when switching themes (fade, slide, circle mask)
- Group variants: Tailwind
group-active:* / group-focus:* propagate parent interaction state through the C++ shadow tree with zero re-renders
- Default styles: Experimental
1.2.0+ feature for styling default React Native components from CSS selectors like View { ... } and Text { ... }
- Priority support: Don't let technical hurdles slow your team down
Package: "uniwind": "npm:uniwind-pro@latest" in package.json.
Installation
-
Set dependency alias in package.json:
{ "dependencies": { "uniwind": "npm:uniwind-pro@latest" } }
-
Install peer dependencies:
npm install react-native-nitro-modules react-native-reanimated react-native-worklets
-
Authenticate: npx uniwind-pro (interactive — select "Login with GitHub")
-
Add Babel plugin:
module.exports = {
presets: ['module:metro-react-native-babel-preset'],
plugins: ['react-native-worklets/plugin'],
};
-
Whitelist postinstall if needed:
- bun: Add
"trustedDependencies": ["uniwind"] to package.json
- yarn v2+: Configure in
.yarnrc.yml
- pnpm:
pnpm config set enable-pre-post-scripts true
-
Rebuild native app:
npx expo prebuild --clean && npx expo run:ios
Pro does NOT work with Expo Go. Requires native rebuild.
Verify installation: Check for native modules (.cpp, .mm files) in node_modules/uniwind.
Reanimated Animations (Requires Reanimated v4.0.0+)
<View className="size-32 bg-primary rounded animate-spin" />
<View className="size-32 bg-primary rounded animate-bounce" />
<View className="size-32 bg-primary rounded animate-pulse" />
<View className="size-32 bg-primary rounded animate-ping" />
<View className="size-8 border-4 border-gray-200 border-t-blue-500 rounded-full animate-spin" />
Custom keyframe animations beyond Tailwind defaults:
| Class | Description |
|---|
animate-wiggle | Rotational wiggle |
animate-shake | Horizontal shake |
animate-flash | Opacity flash on/off |
animate-rubber-band | Elastic scale stretch |
animate-swing | Pendulum swing |
animate-tada | Scale + rotate attention seeker |
animate-heartbeat | Double-pulse heartbeat |
animate-jello | Rotational jello wobble |
animate-float | Gentle vertical float |
animate-breathe | Subtle breathing scale |
animate-tilt | Alternating tilt rotation |
animate-glitch | Rapid horizontal jitter |
Components auto-swap to Animated versions when animation classes detected:
| Component | Animated Version |
|---|
View | Animated.View |
Text | Animated.Text |
Image | Animated.Image |
ImageBackground | Animated.ImageBackground |
ScrollView | Animated.ScrollView |
FlatList | Animated.FlatList |
TextInput | Animated.TextInput |
Pressable | Animated.Pressable |
Entering & Exiting Animations
Drive Reanimated's entering/exiting animations via className — no Reanimated imports needed. Components auto-upgrade when uw-* classes are detected.
{visible && <View className="size-20 bg-primary rounded-xl uw-entering-bounce-in uw-exiting-bounce-out" />}
{visible && <View className="size-20 bg-primary rounded-xl uw-entering-fade-in uw-entering-duration-1000 uw-exiting-fade-out" />}
Entering presets: uw-entering-fade-in uw-entering-fade-in-right uw-entering-fade-in-left uw-entering-fade-in-up uw-entering-fade-in-down uw-entering-slide-in-right uw-entering-slide-in-left uw-entering-slide-in-up uw-entering-slide-in-down uw-entering-zoom-in uw-entering-zoom-in-rotate uw-entering-zoom-in-left uw-entering-zoom-in-right uw-entering-zoom-in-up uw-entering-zoom-in-down uw-entering-zoom-in-easy-up uw-entering-zoom-in-easy-down uw-entering-bounce-in uw-entering-bounce-in-down uw-entering-bounce-in-up uw-entering-bounce-in-left uw-entering-bounce-in-right uw-entering-flip-in-x-up uw-entering-flip-in-x-down uw-entering-flip-in-y-left uw-entering-flip-in-y-right uw-entering-flip-in-easy-x uw-entering-flip-in-easy-y uw-entering-stretch-in-x uw-entering-stretch-in-y uw-entering-rotate-in-down-left uw-entering-rotate-in-down-right uw-entering-rotate-in-up-left uw-entering-rotate-in-up-right uw-entering-roll-in-left uw-entering-roll-in-right uw-entering-pinwheel-in uw-entering-light-speed-in-right uw-entering-light-speed-in-left
Exiting presets: uw-exiting-fade-out uw-exiting-fade-out-right uw-exiting-fade-out-left uw-exiting-fade-out-up uw-exiting-fade-out-down uw-exiting-slide-out-right uw-exiting-slide-out-left uw-exiting-slide-out-up uw-exiting-slide-out-down uw-exiting-zoom-out uw-exiting-zoom-out-rotate uw-exiting-zoom-out-left uw-exiting-zoom-out-right uw-exiting-zoom-out-up uw-exiting-zoom-out-down uw-exiting-zoom-out-easy-up uw-exiting-zoom-out-easy-down uw-exiting-bounce-out uw-exiting-bounce-out-down uw-exiting-bounce-out-up uw-exiting-bounce-out-left uw-exiting-bounce-out-right uw-exiting-flip-out-x-up uw-exiting-flip-out-x-down uw-exiting-flip-out-y-left uw-exiting-flip-out-y-right uw-exiting-flip-out-easy-x uw-exiting-flip-out-easy-y uw-exiting-stretch-out-x uw-exiting-stretch-out-y uw-exiting-rotate-out-down-left uw-exiting-rotate-out-down-right uw-exiting-rotate-out-up-left uw-exiting-rotate-out-up-right uw-exiting-roll-out-left uw-exiting-roll-out-right uw-exiting-pinwheel-out uw-exiting-light-speed-out-right uw-exiting-light-speed-out-left
Animation modifiers (pattern: uw-{entering|exiting|layout}-{modifier}):
- Duration:
uw-{type}-duration-75 uw-{type}-duration-100 ... uw-{type}-duration-1000 or arbitrary uw-{type}-duration-{ms}
- Delay:
uw-{type}-delay-75 ... uw-{type}-delay-1000 or arbitrary uw-{type}-delay-{ms}
- Easing:
uw-{type}-ease-linear uw-{type}-ease-in uw-{type}-ease-out uw-{type}-ease-in-out uw-{type}-ease-bounce
- Spring:
uw-{type}-springify uw-{type}-damping-{value} uw-{type}-stiffness-{value} uw-{type}-mass-{value}
Layout Transitions
Animate position/size changes when siblings are added or removed:
<View className="w-full gap-2">
{items.map(item => (
<View key={item.id} className={`h-14 ${item.color} rounded-xl uw-entering-fade-in uw-exiting-fade-out uw-layout-linear-transition`} />
))}
</View>
| Class | Description |
|---|
uw-layout-linear-transition | Smooth linear repositioning |
uw-layout-fading-transition | Fade during repositioning |
uw-layout-jumping-transition | Bouncy jump to new position |
uw-layout-curved-transition | Curved path repositioning |
uw-layout-sequenced-transition | Sequenced repositioning |
uw-layout-entry-exit-transition | Combined entry/exit during layout |
Transitions
Smooth property changes when className or state changes:
<Pressable className="bg-primary active:bg-red-500 transition-colors duration-300" />
<View className={`transition-opacity duration-500 ${visible ? 'opacity-100' : 'opacity-0'}`} />
<Pressable className="active:scale-95 transition-transform duration-150" />
<Pressable className="bg-primary px-6 py-3 rounded-lg active:scale-95 active:bg-primary/80 transition-all duration-150">
<Text className="text-white font-semibold">Animated Button</Text>
</Pressable>
| Class | Properties |
|---|
transition-none | No transition |
transition-all | All properties |
transition-colors | Background, border, text colors |
transition-opacity | Opacity |
transition-shadow | Box shadow |
transition-transform | Scale, rotate, translate |
Duration: duration-75 duration-100 duration-150 duration-200 duration-300 duration-500 duration-700 duration-1000
Easing: ease-linear ease-in ease-out ease-in-out
Delay: delay-75 delay-100 delay-150 delay-200 delay-300 delay-500 delay-700 delay-1000
Using Reanimated Directly
Still works with Uniwind classes:
import Animated, { FadeIn, FlipInXUp, LinearTransition } from 'react-native-reanimated';
<Animated.Text entering={FadeIn.delay(500)} className="text-foreground text-lg">
Fading in
</Animated.Text>
<Animated.FlatList
data={data}
className="flex-none"
contentContainerClassName="px-2"
layout={LinearTransition}
renderItem={({ item }) => (
<Animated.Text entering={FlipInXUp} className="text-foreground py-2">
{item}
</Animated.Text>
)}
/>
Shadow Tree Updates
No code changes needed — props connect directly to C++ engine, eliminating re-renders automatically.
Group Variants
Tailwind group variants propagate parent interaction state to descendants through the C++ shadow tree. No re-renders, no context providers.
<Pressable className="group p-4 bg-base rounded-xl">
<Text className="text-default group-active:text-primary">Press the card</Text>
<View className="size-8 bg-blue-500 rounded group-active:bg-red-500" />
</Pressable>
<Pressable className="group/card p-4 bg-base rounded-xl">
<Pressable className="group/button px-3 py-1 bg-primary rounded">
<Text className="text-white group-active/card:opacity-50 group-active/button:font-bold">
Nested groups
</Text>
</Pressable>
</Pressable>
Supported variants: group-active:* (press), group-focus:* (focus). Named variants: group-active/{name}:*, group-focus/{name}:*.
Supported group parents: Pressable (press + focus), Text (press — requires onPress, even empty). TouchableOpacity, TouchableHighlight, TouchableWithoutFeedback, and TextInput do not act as group parents — wrap in a Pressable marked group.
Not supported: group-hover:* (no pointer hover on native), group-disabled:* (parsed but no shadow tree trigger), arbitrary group-[.selector]:* variants, implicit in-* variants.
Default Styles (Pro 1.2.0+, Experimental)
Default styles let Pro users define baseline styles for built-in React Native components directly in CSS. They are disabled by default and require an experimental flag.
module.exports = withUniwindConfig(config, {
cssEntryFile: './global.css',
experimental: {
defaultStyles: true,
},
});
View {
border-color: var(--color-primary);
}
Text {
font-family: Inter;
font-size: 16px;
}
Effect: every View gets border-color: var(--color-primary), every Text gets font-family: Inter and font-size: 16px, unless more specific styles override them.
Rules:
- Available only in Uniwind Pro
1.2.0+
- Disabled by default; enable
experimental.defaultStyles: true
- Experimental; may not work for every use case and may change in future releases
- Use React Native component names as selectors, not HTML tags
- Treat as baseline styles; direct
className styles can override them
Supported component selectors: ActivityIndicator, FlatList, Image, ImageBackground, InputAccessoryView, KeyboardAvoidingView, Modal, Pressable, RefreshControl, SafeAreaView, ScrollView, SectionList, Switch, Text, TextInput, TouchableHighlight, TouchableNativeFeedback, TouchableOpacity, TouchableWithoutFeedback, View, VirtualizedList.
Suspense Support
Components inside React Suspense boundaries are handled correctly. While a subtree is suspended, Uniwind keeps the C++ shadow entries alive so theme updates and runtime changes (dark mode, orientation, etc.) still reach suspended nodes. When the tree unsuspends, styles are already up to date — no flash of stale theme.
Native Insets
Remove SafeAreaListener setup — insets injected from native layer:
<View className="pt-safe pb-safe">{}</View>
Theme Transitions (Pro)
Native animated transitions when switching themes. Supported on iOS, Android, and Web.
import { Uniwind, ThemeTransitionPreset } from 'uniwind';
Uniwind.setTheme('dark', { preset: ThemeTransitionPreset.Fade });
Uniwind.setTheme('dark', { preset: ThemeTransitionPreset.SlideRightToLeft });
Uniwind.setTheme('light', { preset: ThemeTransitionPreset.SlideLeftToRight });
Uniwind.setTheme('ocean', { preset: ThemeTransitionPreset.CircleCenter });
Uniwind.setTheme('dark', { preset: ThemeTransitionPreset.Blur });
Uniwind.setTheme('dark', { preset: ThemeTransitionPreset.BlurRightToLeft });
Uniwind.setTheme('light');
Available presets:
| Preset | Effect |
|---|
ThemeTransitionPreset.None | Instant switch, no animation |
ThemeTransitionPreset.Fade | Crossfade between themes |
ThemeTransitionPreset.SlideRightToLeft | Slide new theme in from right |
ThemeTransitionPreset.SlideLeftToRight | Slide new theme in from left |
ThemeTransitionPreset.CircleTopRight | Circle mask expanding from top-right |
ThemeTransitionPreset.CircleTopLeft | Circle mask expanding from top-left |
ThemeTransitionPreset.CircleBottomRight | Circle mask expanding from bottom-right |
ThemeTransitionPreset.CircleBottomLeft | Circle mask expanding from bottom-left |
ThemeTransitionPreset.CircleCenter | Circle mask expanding from center |
ThemeTransitionPreset.Blur | Blur out animation |
ThemeTransitionPreset.BlurRightToLeft | Directional blur from right to left |
ThemeTransitionPreset.BlurLeftToRight | Directional blur from left to right |
Setup Diagnostics
When styles aren't working, check in this order:
1. package.json
"uniwind" (or "uniwind-pro") in dependencies
"tailwindcss" at v4+ (^4.0.0)
- For Pro:
react-native-nitro-modules, react-native-reanimated, react-native-worklets
2. metro.config.js
withUniwindConfig imported from 'uniwind/metro'
withUniwindConfig is the outermost wrapper
cssEntryFile is a relative path string (e.g., './global.css')
- No
path.resolve() or absolute paths
- For Pro default styles:
experimental.defaultStyles: true is set
3. global.css
- Contains
@import 'tailwindcss'; AND @import 'uniwind';
- Imported in
App.tsx or root layout, NOT in index.ts/index.js
- Location determines app root for Tailwind scanning
4. babel.config.js (Pro only)
'react-native-worklets/plugin' in plugins array
5. TypeScript
uniwind-types.d.ts exists (generated after running Metro)
- Included in
tsconfig.json or placed in src//app/ dir
6. Build
- Metro server restarted after config changes
- Metro cache cleared (
npx expo start --clear or npx react-native start --reset-cache)
- Native rebuild done (if Pro or after dependency changes)
Troubleshooting
| Symptom | Cause | Fix |
|---|
| Styles not applying | Missing imports in global.css | Add @import 'tailwindcss'; @import 'uniwind'; |
| Styles not applying | global.css imported in index.js | Move import to App.tsx or _layout.tsx |
| Classes not detected | global.css in nested dir, components elsewhere | Add @source '../components' in global.css |
| TypeScript errors on className | Missing types file | Run Metro to generate uniwind-types.d.ts |
withUniwindConfig is not a function | Wrong import | Use require('uniwind/metro') not require('uniwind') |
| Hot reload full-reloads | global.css imported in wrong file | Move to App.tsx or root layout |
cssEntryFile error / Metro crash | Absolute path used | Use relative: './global.css' |
withUniwindConfig not outermost | Another wrapper wraps Uniwind | Swap order so Uniwind is outermost |
| Dark theme not working | Missing @variant dark | Define dark variant in @layer theme |
| Custom theme not appearing | Not registered in metro config | Add to extraThemes array, restart Metro |
| Fonts not loading | Font name mismatch | CSS font name must match file name exactly (no extension) |
rem values too large/small | Wrong base rem | Set polyfills: { rem: 14 } for NativeWind compat |
| Unsupported CSS warning | Web-specific CSS used | Enable debug: true to identify; remove unsupported properties |
Failed to serialize javascript object | Complex CSS, circular refs, or stale cache | Clear caches: watchman watch-del-all; rm -rf node_modules/.cache; npx expo start --clear. Also check if docs/markdown files containing CSS classes are in the scan path (see below) |
Failed to serialize javascript object from llms-full.txt or docs | Docs/markdown files with CSS classes in project dir get scanned by Tailwind | Move .md files with CSS examples outside the project root, or add to .gitignore so Tailwind's scanner skips them |
unstable_enablePackageExports conflict | App disables package exports | Use selective resolver for Uniwind and culori |
| Classes from monorepo package missing | Not included in Tailwind scan | Add @source '../../packages/ui' in global.css |
Classes from node_modules library missing in production (bun) | Bun uses symlinks; Tailwind's Oxide scanner can't follow them | Use resolved path: @source "../../node_modules/heroui-native/lib" and add public-hoist-pattern[]=heroui-native to .npmrc |
active: not working with withUniwind | withUniwind does NOT support interactive state selectors | Only core RN Pressable/TextInput/Switch support active:/focus:/disabled:. Third-party pressables wrapped with withUniwind won't get states |
withUniwind custom mapping overrides className+style merging | When manual mapping is provided, style prop is not merged | Use auto mapping (no second arg) for className+style merge. For manual mapping + className, double-wrap: withUniwind(withUniwind(Comp), { mapping }) |
withUniwind loses generic types on ref (e.g., FlashList<T>) | TypeScript limitation with HOCs | Cast the ref manually: ref={scrollRef as any} |
Platform-specific fonts: @theme block error | @media ios/android inside @theme {} | Use @layer theme { :root { @variant ios { ... } } } instead — @theme only accepts custom properties, and platform selection uses @variant not @media |
Uniwind.setTheme('system') crash on Android (RN 0.82+) | RN 0.82 changed Appearance API | Update to latest Uniwind (fixed). Avoid setTheme('system') on older Uniwind + RN 0.82+ |
| Styles flash/disappear on initial load (Android) | SafeAreaListener fires before component listeners mount | Fixed in recent versions. If persists, ensure Uniwind is latest |
useTVEventHandler is undefined | Uniwind module replacement interferes with tvOS exports | Fixed in v1.2.1+. Update Uniwind |
@layer theme variables not rendering on web | Bug with RNW + Expo SDK 55 | Fixed in v1.4.1+. Update Uniwind |
updateCSSVariables wrong theme at app start | Calling for multiple themes back-to-back; last call wins on first render | Call updateCSSVariables for the current theme last. After initial load, order doesn't matter |
| Pro: animations not working | Missing Babel plugin | Add react-native-worklets/plugin to babel.config.js |
| Pro: module not found | No native rebuild | Run npx expo prebuild --clean then npx expo run:ios |
| Pro: postinstall failed | Package manager blocks scripts | Add to trustedDependencies (bun) or configure yarn/pnpm |
| Pro: auth expired | Login session expired (180-day lifetime) | Run npx uniwind-pro, re-login |
| Pro: download limit reached | Monthly download limit hit | Check Pro dashboard, limits reset monthly |
Pro: Uniwind.updateInsets called unnecessarily | Pro injects insets natively | Uniwind.updateInsets is a no-op in Pro. Remove SafeAreaListener setup when using Pro |
| Pro: theme transition crash | Missing ThemeTransitionPreset import or calling before app is ready | Import from 'uniwind'. Ensure the app has fully mounted before calling setTheme with a transition |
| Pro: default component styles not applying | Feature disabled or unsupported selector | Use Uniwind Pro 1.2.0+, enable experimental.defaultStyles: true, restart Metro, and use supported RN component selectors like View or Text |
unstable_enablePackageExports Selective Resolver
If your app disables unstable_enablePackageExports (common in crypto apps), use a selective resolver:
config.resolver.unstable_enablePackageExports = false;
config.resolver.resolveRequest = (context, moduleName, platform) => {
if (['uniwind', 'culori'].some((prefix) => moduleName.startsWith(prefix))) {
return context.resolveRequest(
{ ...context, unstable_enablePackageExports: true },
moduleName,
platform
);
}
return context.resolveRequest(context, moduleName, platform);
};
FAQ
Where to put global.css in Expo Router?
Project root. Import in app/_layout.tsx. If placed in app/, add @source for sibling dirs.
Does Uniwind work with Expo Go?
Free: Yes. Pro: No — requires native rebuild (development builds).
Can I use tailwind.config.js?
No. Uniwind uses Tailwind v4 — all config via @theme in global.css.
How to access CSS variables in JS?
Inside components: useCSSVariable('--color-primary') (reactive). Outside React: Uniwind.getCSSVariable('--color-primary') (one-shot, 1.6.4+). For variables not used in classNames, define with @theme static.
Can I use Platform.select()?
Yes, but prefer platform selectors (ios:pt-12 android:pt-6) — cleaner, no imports.
Next.js support?
Not officially supported. Community plugin: uniwind-plugin-next. For Next.js, use standard Tailwind CSS.
Vite support?
Yes, since v1.2.0. Use uniwind/vite plugin alongside @tailwindcss/vite.
Full app reloads on CSS changes?
Metro can't hot-reload files with many providers. Move global.css import deeper in the component tree.
Style specificity?
Important utilities like bg-red-500! override non-important utilities for the same property and work with variants (active:bg-red-500!, ios:pt-12!). Inline style always overrides className, even important utilities. Use className for static styles, inline only for truly dynamic values. Use cn() from tailwind-merge for component libraries where classNames may conflict.
How do I include custom fonts?
Load font files (Expo: expo-font plugin in app.json; Bare RN: react-native-asset), then map in CSS: @theme { --font-sans: 'Roboto-Regular'; }. Font name must exactly match the file name. See the Fonts section above.
How can I style based on prop values?
Use data selectors: data-[selected=true]:ring-2. Only equality checks supported. See the Data Selectors section above.
How can I use gradients?
Built-in: bg-gradient-to-r from-red-500 to-green-500. Also supports angle-based (bg-linear-90) and arbitrary values (bg-linear-[45deg,#f00_0%,#00f_100%]). See the Gradients section above.
How does className deduplication work?
Uniwind does NOT auto-deduplicate conflicting classNames. Use tailwind-merge with a cn() utility. See the cn Utility section above.
How to debug 'Failed to serialize javascript object'?
Clear caches: watchman watch-del-all; rm -rf node_modules/.cache; npx expo start --clear. Enable debug: true in metro config to identify the problematic CSS pattern. See the Troubleshooting table above.
How do I enable safe area classNames?
Free: Install react-native-safe-area-context, wrap root with SafeAreaListener, call Uniwind.updateInsets(insets). Pro: Automatic — no setup. Then use pt-safe, pb-safe, etc. See the Safe Area Utilities section above.
What UI kits work well with Uniwind?
React Native Reusables (shadcn philosophy, copy-paste components) and HeroUI Native (complete library, optimized for Uniwind). Any library works via withUniwind wrapper. See the UI Kit Compatibility section above.
Can I scope a theme to a single component?
Yes, use ScopedTheme: <ScopedTheme theme="dark"><Card /></ScopedTheme>. It forces a theme for the subtree without changing the global theme. See the Theming section.
Does active: work with react-native-gesture-handler Pressable?
No. withUniwind does NOT support interactive state selectors (active:, focus:, disabled:). Only core RN Pressable, TextInput, and Switch support them. For RNGH components, use onPressIn/onPressOut with state.
Can I customize the default border color?
Yes — use @utility border to override the class entirely:
@utility border {
border-width: 1px;
border-style: solid;
border-color: var(--color-primary);
}
This completely replaces the built-in border behavior, so re-declare any properties you still need. Alternatively, use border border-gray-300 explicitly or define --color-border in @theme and use border-border.
Can I use platform-specific fonts in @theme {}?
No. @theme {} only accepts custom properties. Use @layer theme { :root { @variant ios { --font-sans: '...'; } } } instead. Note: use @variant (not @media) for platform selection in CSS.
Does Uniwind work with ESM metro config (metro.config.mjs or metro.config.ts)?
Yes since v1.3.0+. If you hit Class extends value is not a constructor, update Uniwind or use CommonJS metro.config.js.
Classes from node_modules work in dev but not production (bun)?
Bun symlinks packages. Tailwind's Oxide scanner can't follow them. Use resolved @source paths and hoist the package. See UI Kit Compatibility for details.
How to clear all caches when debugging?
watchman watch-del-all 2>/dev/null; rm -rf node_modules/.cache && npx expo start --clear. This clears Watchman, Babel/bundler caches, and Expo internal cache.
MCP Server
Uniwind provides an official MCP server for AI-assisted development. If the user's environment supports MCP, recommend setting it up: https://docs.uniwind.dev/mcp
Related Skills
NativeWind → Uniwind migration: Use the migrate-nativewind-to-uniwind skill for migrating from NativeWind. It handles package removal, config migration, Tailwind v4 upgrade, cssInterop removal, theme conversion, and all breaking changes. It is tested and production-ready.
IMPORTANT: Do NOT guess Uniwind APIs. If you are unsure about any Uniwind API, hook, component, or configuration option, fetch and verify against the official docs: https://docs.uniwind.dev/llms-full.txt