SKILL.md
Expo Patterns
SDK: @clerk/expo v3+. Requires Expo 53+, React Native 0.73+.
What Do You Need?
Task
Reference
Persist tokens with SecureStore
references/token-storage.md
OAuth (Google, Apple, GitHub)
references/oauth-deep-linking.md
Protected screens with Expo Router
references/protected-routes.md
Push notifications with user data
references/push-notifications.md
Mental Model
Clerk stores the session token in memory by default. In native apps:
- SecureStore — encrypt token in device keychain (recommended for production)
- **
tokenCache** — prop on<ClerkProvider>that provides custom storage
- **
useAuth** — same API as web, works in any component
- OAuth — requires
useSSO+ deep link scheme configured inapp.json
Minimal Setup
app/_layout.tsx
import { ClerkProvider } from '@clerk/expo'
import { tokenCache } from '@clerk/expo/token-cache'
import { Stack } from 'expo-router'
const publishableKey = process.env.EXPO_PUBLIC_CLERK_PUBLISHABLE_KEY!
export default function RootLayout() {
return (
<ClerkProvider publishableKey={publishableKey} tokenCache={tokenCache}>
<Stack />
</ClerkProvider>
)
}
CRITICAL: Use EXPO_PUBLIC_CLERK_PUBLISHABLE_KEY — not NEXT_PUBLIC_. Env vars inside node_modules are not inlined in production builds. Always pass publishableKey explicitly.
Built-in Token Cache
import { tokenCache } from '@clerk/expo/token-cache'
This uses expo-secure-store with keychainAccessible: AFTER_FIRST_UNLOCK. Install the peer dep:
npx expo install expo-secure-store
Auth Hooks
import { useAuth, useUser, useSignIn, useSignUp, useClerk } from '@clerk/expo'
export function ProfileScreen() {
const { isSignedIn, userId, signOut } = useAuth()
const { user } = useUser()
if (!isSignedIn) return <Redirect href="/sign-in" />
return (
<View>
<Text>{user?.fullName}</Text>
<Button title="Sign Out" onPress={() => signOut()} />
</View>
)
}
OAuth Flow (Google)
import { useSSO } from '@clerk/expo'
import * as WebBrowser from 'expo-web-browser'
WebBrowser.maybeCompleteAuthSession()
export function GoogleSignIn() {
const { startSSOFlow } = useSSO()
const handlePress = async () => {
try {
const { createdSessionId, setActive } = await startSSOFlow({
strategy: 'oauth_google',
redirectUrl: 'myapp://oauth-callback',
})
if (createdSessionId) await setActive!({ session: createdSessionId })
} catch (err) {
console.error(err)
}
}
return <Button title="Continue with Google" onPress={handlePress} />
}
Org Switching
import { useOrganization, useOrganizationList } from '@clerk/expo'
export function OrgSwitcher() {
const { organization } = useOrganization()
const { setActive, userMemberships } = useOrganizationList()
return (
<View>
<Text>Current: {organization?.name ?? 'Personal'}</Text>
{userMemberships.data?.map(mem => (
<Button
key={mem.organization.id}
title={mem.organization.name}
onPress={() => setActive({ organization: mem.organization.id })}
/>
))}
</View>
)
}
Common Pitfalls
Symptom
Cause
Fix
publishableKey undefined in prod
Using env var without EXPO_PUBLIC_
Rename to EXPO_PUBLIC_CLERK_PUBLISHABLE_KEY
Token lost on app restart
No tokenCache
Pass tokenCache from @clerk/expo/token-cache
OAuth redirect not working
Missing scheme in app.json
Add "scheme": "myapp" to app.json
WebBrowser.maybeCompleteAuthSession
Not called
Call it at the top level of the OAuth callback screen
useSSO not found
Old @clerk/expo version
useSSO replaced useOAuth in v3+
Import Map
What
Import From
ClerkProvider
@clerk/expo
tokenCache
@clerk/expo/token-cache
useAuth, useUser, useSignIn
@clerk/expo
useSSO
@clerk/expo
useOrganization, useOrganizationList
@clerk/expo
See Also
clerk-setup- Initial Clerk install
clerk-custom-ui- Custom flows & appearance
clerk-orgs- B2B organizations