iOS build fails with Swift 6 RawSpan errors on Xcode 16 / Codemagic CI Build error: "Value of type 'RawSpan' has no member 'count'" when integrating via SPM

[superbigroach]

sign_in_with_apple_web 2.1.1 (3.0.0 available)
source_gen 2.0.0 (4.1.1 available)
source_helper 1.3.7 (1.3.9 available)
test_api 0.7.7 (0.7.8 available)
! uuid 4.5.2 (overridden)
video_player_avfoundation 2.8.7 (2.8.8 available)
wallet 0.0.13 (0.0.18 available)
web3dart 2.7.3 (3.0.1 available)
Got dependencies!
1 package is discontinued.
70 packages have newer versions incompatible with dependency constraints.
Try flutter pub outdated for more information.
Archiving com.lucilla.app...
Upgrading AppFrameworkInfo.plist
Upgrading Podfile
Automatically signing iOS for device deployment using specified development team in Xcode project: PQLFKHM37Y
Running pod install... 17.2s
Running Xcode build...
Xcode archive done. 67.0s
Failed to build iOS app
Swift Compiler Error (Xcode): Value of type 'RawSpan' has no member 'count'
/Users/builder/Library/Developer/Xcode/DerivedData/Runner-edaimyiflreloheqntgnhkmwcclv/SourcePackages/checkouts/web3swift/Sources/Web3Core/EthereumABI/ABIElements.swift:473:22

Swift Compiler Error (Xcode): Value of type 'RawSpan' has no subscripts
/Users/builder/Library/Developer/Xcode/DerivedData/Runner-edaimyiflreloheqntgnhkmwcclv/SourcePackages/checkouts/web3swift/Sources/Web3Core/EthereumABI/ABIElements.swift:477:49

Swift Compiler Error (Xcode): Value of type 'RawSpan' has no subscripts
/Users/builder/Library/Developer/Xcode/DerivedData/Runner-edaimyiflreloheqntgnhkmwcclv/SourcePackages/checkouts/web3swift/Sources/Web3Core/EthereumABI/ABIElements.swift:478:56

Swift Compiler Error (Xcode): Cannot convert value of type 'RawSpan' to expected argument type '[UInt8]'
/Users/builder/Library/Developer/Xcode/DerivedData/Runner-edaimyiflreloheqntgnhkmwcclv/SourcePackages/checkouts/web3swift/Sources/Web3Core/Utility/Utilities.swift:251:74

Swift Compiler Error (Xcode): Cannot convert value of type 'RawSpan' to expected argument type '[UInt8]'
/Users/builder/Library/Developer/Xcode/DerivedData/Runner-edaimyiflreloheqntgnhkmwcclv/SourcePackages/checkouts/web3swift/Sources/Web3Core/Utility/Utilities.swift:251:84

Swift Compiler Error (Xcode): Value of type 'RawSpan' has no subscripts
/Users/builder/Library/Developer/Xcode/DerivedData/Runner-edaimyiflreloheqntgnhkmwcclv/SourcePackages/checkouts/web3swift/Sources/Web3Core/Utility/Utilities.swift:278:27

Swift Compiler Error (Xcode): Value of type 'RawSpan' has no subscripts
/Users/builder/Library/Developer/Xcode/DerivedData/Runner-edaimyiflreloheqntgnhkmwcclv/SourcePackages/checkouts/web3swift/Sources/Web3Core/Utility/Utilities.swift:279:27

Swift Compiler Error (Xcode): Value of type 'RawSpan' has no subscripts
/Users/builder/Library/Developer/Xcode/DerivedData/Runner-edaimyiflreloheqntgnhkmwcclv/SourcePackages/checkouts/web3swift/Sources/Web3Core/Utility/Utilities.swift:280:54

Encountered error while archiving for device.

Build failed :|
Step 12 script Flutter build iOS exited with status code 1

[superbigroach]

✅ Update: Issue Resolved with Fixes

I've successfully resolved the Swift 6 compatibility issues and got the SDK building on Xcode 16 /
Codemagic CI. Here's what I found and fixed:

Root Causes

There were two separate Swift 6 compatibility issues:

Issue 1: web3swift Dependency Version

The SDK was pinned to web3swift 3.2.2 which doesn't support Swift 6. Updating to allow 3.3.x
resolves the RawSpan errors.

Issue 2: Missing try on Throwing Property Access

In CircleModularWalletsCore/Sources/Helpers/Utils/Utils.swift at line 97, there's a property access
that can throw in Swift 6 but wasn't marked with try:

// ❌ Original (fails in Swift 6):
let rawClientData = webauthn.clientDataJSON.bytes

// ✅ Fixed:
let rawClientData = try webauthn.clientDataJSON.bytes

Swift 6 enforces stricter error handling, and .bytes on clientDataJSON is now recognized as a
throwing accessor.

Solution

I've created a fork with both fixes applied:
👉 https://github.com/superbigroach/modularwallets-ios-sdk

Commits:

• e69e6c0 - fix: update web3swift to allow 3.3.x for Swift 6 compatibility
• 9aa2a1b - fix: add try? to contract.method for Swift 6 compatibility
• a114a3b - fix: add try to throwing property access for Swift 6 compatibility

Build Result

After applying these fixes:

• ✅ iOS app builds successfully on Codemagic CI with Xcode 16
• ✅ Archive size: 843.9MB → IPA: 72.8MB
• ✅ Passkey wallet creation/login working correctly
• ✅ Published to Firebase App Distribution and tested on device

Recommendation

Please merge these Swift 6 compatibility fixes into the official SDK so other developers don't
encounter the same issues. I'm happy to submit a Pull Request if that would help.

Environment

• Xcode: 16.x (latest)
• Swift: 6.0
• iOS Deployment Target: 16.0
• CI: Codemagic (mac_mini_m1)
• Integration: Swift Package Manager

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