Supabase request failing on iOS 18.4 (iOS Simulator)

[KingOfMac]

Supabase Requests Fail on iOS Simulator After Upgrading to Expo SDK 52

Also Reported On: Supabase Discussion #35041

Description

After upgrading my React Native project to Expo SDK 52, all Supabase-related requests began failing on the iOS Simulator (iPhone 16, iOS 18.4). These requests were functioning correctly on Expo SDK 51, and no changes were made to the Supabase-related code.

Environment

• Supabase JS Client Version: @supabase/supabase-js@^2.49.4
• Platform: iOS Simulator (iPhone 16, iOS 18.4)
• Expo SDK Version: 52
• Environment: React Native (via Expo)
• Supabase Instance: Production Supabase project (not self-hosted)

Issue Scope

All Supabase network requests fail, including:

• auth.signInWithPassword
• Calling edge functions

Error Messages

• AuthRetryableFetchError: Network request failed
• TypeError: Network request failed
• FunctionsFetchError: Failed to send a request to the Edge Function

Notes

• The issue only occurs on the iOS Simulator; functionality on physical devices has not been tested yet.
• Supabase requests work fine in Safari within the Simulator, suggesting it's likely not a real network issue.
• The same Supabase requests work fine in the production app.
• Downgrading the iOS version on the simulator from iOS 18.4 resolves the issue (I tested 18.0).

Supabase Client Configuration

export const supabase = createClient<Database>(SUPABASE_URL, SUPABASE_ANON_KEY, {
  auth: {
    storage: AsyncStorage,
    autoRefreshToken: true,
    persistSession: true,
    detectSessionInUrl: false,
  },
});

export const signInWithEmail = (email: string, password: string) =>
  supabase.auth.signInWithPassword({ email, password });

[bradydowling]

Why is this marked as completed? Is there an update that fixes this?

[KingOfMac]

It's not a supabase issue. It was an IOS Simulator Bug. Apple Support confirmed

[alfjesus]

It's not a supabase issue. It was an IOS Simulator Bug. Apple Support confirmed

Do we have a link to Apple where they confirm this bug?

[evelant]

Can somebody link to the bug with Apple? This was driving me insane. My simulator was just randomly refusing to load assets from supabase storage buckets. Lost a ton of time debugging what I thought was an issue with my app after upgrading to expo53 / react native 0.79 / new architecture, until I realized the sim just wasn't connecting to supabase buckets.

[evelant]

Downgrade the iOS simulator to 18.3. Everything works fine on 18.3, definitely a bug with 18.4 simulator.

[eeston]

Eugh this has been causing me a headache for too long. Thanks for the tip to downgrade the simulator to 18.3...worked a treat.

@evelant @alfjesus there is a post here with some more details....https://developer.apple.com/forums/thread/777999
I think it has been fixed in a recent beta.

[Hallidayo]

Hi all, I'm going to move this over as a discussion as its not a supabase bug by the looks of it. Thanks all for your help on this one.

[eyupk3]

Same problem tested 18.3, 18.2 ios simulator.

"expo": "~53.0.10",
"@supabase/supabase-js": "^2.50.0",

[traviswimer]

If anyone is still seeing this error, upgrading the iOS Simulator to 18.5 seems to fix it. (You'll probably need to upgrade Xcode to install it)

[diogeneshamilton]

Correct, upgrading works- it was insane for me to find this after a day of thinking it was my own fault. I was trying to upload an image to Supabase storage, and this just didn't come up for a while in searches.

[farhanhaider1]

upgrading to ios 18.6 fixed it for me

[heavenstay]

Yep, upgrading to iOS 18.6 works for me. Don’t waste time, just try it on an iOS simulator version other than 18.4.

[DeabitTech]

i still have this error today on ios 26