feat: Extract non-custodial signers setup to allow from the SDK initialization.

Examples/SmartWalletsDemo/SmartWalletsDemo/Dashboard/DashboardView.swift

@@ -2,7 +2,6 @@ import SwiftUI
 import CrossmintClient
 import Wallet
 
-// swiftlint:disable:next type_body_length
 struct DashboardView: View {
     @EnvironmentObject var sdk: CrossmintSDK
 
@@ -20,9 +19,11 @@ struct DashboardView: View {
     @State private var isShaking: Bool = false
     private let hapticFeedback = UINotificationFeedbackGenerator()
 
-    private var authManager: AuthManager {
-        sdk.authManager
-    }
+    // Use this instead of the email signer to enable Passkeys signing.
+    private let passkeySigner: EVMSigners = .passkey(
+        name: "<email to send the otp code>",
+        host: "wallets-ios.demos-crossmint.com"
+    )
 
     enum Tab {
         case balance, transfer, nft
@@ -233,23 +234,10 @@ struct DashboardView: View {
     }
 
     private func obtainOrCreateWallet(_ updateLoadingStatus: Bool = false) async {
-        guard let email = await authManager.email else {
-            await MainActor.run {
-                if updateLoadingStatus {
-                    creatingWallet = false
-                }
-                showAlert(with: "There was a problem creating the wallet.\nLogout and try again.")
-            }
-            return
-        }
-
         do {
             let wallet = try await sdk.crossmintWallets.getOrCreateWallet(
                 chain: .baseSepolia,
-                signer: .passkey(
-                    name: email,
-                    host: "wallets-ios.demos-crossmint.com"
-                )
+                signer: .email
             )
 
             await MainActor.run {

Examples/SmartWalletsDemo/SmartWalletsDemo/Dashboard/TransferDashboardView.swift

@@ -19,6 +19,8 @@ struct TransferDashboardView: View {
     @State private var showTokenSelectionMenu: Bool = false
     @State private var isSendingTransaction: Bool = false
 
+    @State private var nonCustodialSignerCallback: NonCustodialSignerCallback?
+
     private let evmBlockchain: EVMChain = .baseSepolia
 
     var body: some View {
@@ -110,6 +112,17 @@ struct TransferDashboardView: View {
         .padding()
         .frame(maxWidth: .infinity, maxHeight: .infinity)
         .background(Color(UIColor.systemBackground))
+        .crossmintNonCustodialSigners(sdk, presentingCallback: $nonCustodialSignerCallback)
+        .sheet(item: $nonCustodialSignerCallback) { callback in
+            OTPValidatorView(nonCustodialSignerCallback: callback)
+        }
+        /*
+         These two lines above could be replaced with if the sheet is good enough to render the OTP view:
+
+        .crossmintNonCustodialSignersSheet(sdk, otpView: { callback in
+            OTPValidatorView(nonCustodialSignerCallback: callback)
+        })
+         */
         .onChange(of: balances) { _, newValue in
             if let newValue {
                 // Collect all available tokens with balance

Examples/SmartWalletsDemo/SmartWalletsDemo/NonCustodialSigners/OTPValidatorView.swift

@@ -78,10 +78,3 @@ struct OTPValidatorView: NonCustodialSignerCallbackView {
         showAlert = true
     }
 }
-
-#Preview {
-    OTPValidatorView(
-        nonCustodialSignerCallback: NonCustodialSignerCallback.noOp
-    )
-    .environmentObject(CrossmintSDK.shared)
-}

Sources/CrossmintClient/SwiftUI/CrossmintEnvironment.swift

@@ -11,13 +11,10 @@ extension View {
     public func crossmintEnvironmentObject(
         _ sdk: CrossmintSDK
     ) -> some View {
-        ZStack {
-            self.environmentObject(sdk)
-        }.onAppear {
-            Logger.sdk.info("Initializing the environment without non-custodial signers setup. This might cause trouble if a signer of that type is required later on.")
-        }
+        self.environmentObject(sdk)
     }
 
+    @available(*, deprecated, message: "Use the view modifier on the view that will be requiring non-custodial signing operations.")
     public func crossmintEnvironmentObject<NCSView: NonCustodialSignerCallbackView>(
         _ sdk: CrossmintSDK,
         @ViewBuilder ncsViewBuilder: (NonCustodialSignerCallback) -> NCSView

Sources/CrossmintClient/SwiftUI/CrossmintSDK.swift

@@ -34,7 +34,7 @@ final public class CrossmintSDK: ObservableObject {
     public let authManager: AuthManager
     public let crossmintService: CrossmintService
 
-    let crossmintTEE: CrossmintTEE
+    public let crossmintTEE: CrossmintTEE
 
     public var isProductionEnvironment: Bool {
         crossmintService.isProductionEnvironment

Sources/CrossmintClient/SwiftUI/View+NonCustodialSigners.swift

@@ -0,0 +1,90 @@
+import SwiftUI
+
+private struct HiddenEmailSignersView: View {
+    private var crossmintTEE: CrossmintTEE
+
+    init(crossmintTEE: CrossmintTEE) {
+        self.crossmintTEE = crossmintTEE
+    }
+
+    var body: some View {
+        EmailSignersView(
+            webViewCommunicationProxy: crossmintTEE.webProxy
+        )
+        .frame(width: 1, height: 1)
+        .allowsHitTesting(false)
+        .accessibilityHidden(true)
+        .task {
+            try? await crossmintTEE.load()
+        }
+    }
+}
+
+private struct CrossmintNonCustodialSignerViewModifier: ViewModifier {
+    @ObservedObject private var crossmintTEE: CrossmintTEE
+    @Binding private var presentingCallback: NonCustodialSignerCallback?
+
+    init(sdk: CrossmintSDK, presentingCallback: Binding<NonCustodialSignerCallback?>) {
+        crossmintTEE = sdk.crossmintTEE
+        _presentingCallback = presentingCallback
+    }
+
+    func body(content: Content) -> some View {
+        ZStack {
+            HiddenEmailSignersView(crossmintTEE: crossmintTEE)
+            content
+        }
+        .onChange(of: crossmintTEE.isOTPRequired) { newValue in
+            if newValue {
+                presentingCallback = crossmintTEE.getCallback()
+            } else {
+                presentingCallback = nil
+            }
+        }
+    }
+}
+
+private struct CrossmintNonCustodialSignerSheetModifier<OTPView: NonCustodialSignerCallbackView>: ViewModifier {
+    @ObservedObject private var crossmintTEE: CrossmintTEE
+    private let otpView: (NonCustodialSignerCallback) -> OTPView
+
+    @State private var callback: NonCustodialSignerCallback?
+
+    init(sdk: CrossmintSDK, @ViewBuilder otpView: @escaping (NonCustodialSignerCallback) -> OTPView) {
+        crossmintTEE = sdk.crossmintTEE
+        self.otpView = otpView
+    }
+
+    func body(content: Content) -> some View {
+        ZStack {
+            HiddenEmailSignersView(crossmintTEE: crossmintTEE)
+            content
+        }
+        .onChange(of: crossmintTEE.isOTPRequired) { newValue in
+            callback = newValue ? crossmintTEE.getCallback() : nil
+        }
+        .sheet(item: $callback) { cb in
+            otpView(cb)
+        }
+    }
+}
+
+extension View {
+    public func crossmintNonCustodialSigners(
+        _ sdk: CrossmintSDK,
+        presentingCallback: Binding<NonCustodialSignerCallback?>
+    ) -> some View {
+        self.modifier(
+            CrossmintNonCustodialSignerViewModifier(sdk: sdk, presentingCallback: presentingCallback)
+        )
+    }
+
+    public func crossmintNonCustodialSignersSheet<Content: NonCustodialSignerCallbackView>(
+        _ sdk: CrossmintSDK,
+        @ViewBuilder otpView: @escaping (NonCustodialSignerCallback) -> Content
+    ) -> some View {
+        self.modifier(
+            CrossmintNonCustodialSignerSheetModifier(sdk: sdk, otpView: otpView)
+        )
+    }
+}

Sources/Wallet/DefaultCrossmintWallets.swift

@@ -67,17 +67,6 @@ public final class DefaultCrossmintWallets: CrossmintWallets, Sendable {
             throw .walletGeneric("Unknown wallet chain")
         }
 
-        do {
-            try await (signer as? any EmailSigner)?.load()
-        } catch {
-            Logger.smartWallet.warn(
-                """
-There was an error initializing the Email signer. \(error.errorDescription)
-Review if the .crossmintEnvironmentObject modifier is used as expected.
-"""
-            )
-        }
-
         return wallet
     }
 

Sources/Wallet/Model/Wallet/Wallet.swift

@@ -229,6 +229,11 @@ open class Wallet: @unchecked Sendable {
                 )
             }
         }
+
+        if let email = config.adminSigner as? any EmailSigner {
+            try? await email.load()
+            updatedSigner = email
+        }
         return updatedSigner
     }
 

Sources/Wallet/NonCustodialSignerCallback.swift

@@ -1,4 +1,7 @@
-public struct NonCustodialSignerCallback {
+import Foundation
+
+public struct NonCustodialSignerCallback: Identifiable {
+    public let id = UUID()
     public let otpCode: (String) -> Void
     public let otpCancelled: () -> Void
 

Sources/Wallet/TEEAuthProvider.swift

@@ -0,0 +1,10 @@
+import Foundation
+import Auth
+
+// Minimal auth abstraction for TEE usage without full AuthManager integration
+public protocol TEEAuthProvider: Sendable {
+    var jwt: String? { get async }
+    var email: String? { get async }
+}
+
+extension AuthManager where Self: TEEAuthProvider {}