diff --git a/Thirdweb.Console/Program.cs b/Thirdweb.Console/Program.cs
index a9737bc..73a83e6 100644
--- a/Thirdweb.Console/Program.cs
+++ b/Thirdweb.Console/Program.cs
@@ -325,6 +325,18 @@
 
 #endregion
 
+#region Backend Wallet Auth
+
+// var inAppWalletBackend = await InAppWallet.Create(client: client, authProvider: AuthProvider.Backend, walletSecret: "very-secret");
+// if (!await inAppWalletBackend.IsConnected())
+// {
+//     _ = await inAppWalletBackend.LoginWithBackend();
+// }
+// var inAppWalletBackendAddress = await inAppWalletBackend.GetAddress();
+// Console.WriteLine($"InAppWallet Backend address: {inAppWalletBackendAddress}");
+
+#endregion
+
 #region Account Linking
 
 // var inAppWalletMain = await InAppWallet.Create(client: client, authProvider: AuthProvider.Telegram);
diff --git a/Thirdweb/Thirdweb.Wallets/InAppWallet/EcosystemWallet/EcosystemWallet.cs b/Thirdweb/Thirdweb.Wallets/InAppWallet/EcosystemWallet/EcosystemWallet.cs
index 8918153..622b5b5 100644
--- a/Thirdweb/Thirdweb.Wallets/InAppWallet/EcosystemWallet/EcosystemWallet.cs
+++ b/Thirdweb/Thirdweb.Wallets/InAppWallet/EcosystemWallet/EcosystemWallet.cs
@@ -25,6 +25,7 @@ public partial class EcosystemWallet : IThirdwebWallet
     internal readonly string PhoneNumber;
     internal readonly string AuthProvider;
     internal readonly string LegacyEncryptionKey;
+    internal readonly string WalletSecret;
 
     internal string Address;
 
@@ -46,7 +47,8 @@ internal EcosystemWallet(
         string phoneNumber,
         string authProvider,
         IThirdwebWallet siweSigner,
-        string legacyEncryptionKey
+        string legacyEncryptionKey,
+        string walletSecret
     )
     {
         this.Client = client;
@@ -59,6 +61,7 @@ string legacyEncryptionKey
         this.PhoneNumber = phoneNumber;
         this.AuthProvider = authProvider;
         this.SiweSigner = siweSigner;
+        this.WalletSecret = walletSecret;
     }
 
     #region Creation
@@ -75,6 +78,7 @@ string legacyEncryptionKey
     /// <param name="storageDirectoryPath">The path to the storage directory.</param>
     /// <param name="siweSigner">The SIWE signer wallet for SIWE authentication.</param>
     /// <param name="legacyEncryptionKey">The encryption key that is no longer required but was used in the past. Only pass this if you had used custom auth before this was deprecated.</param>
+    /// <param name="walletSecret">The wallet secret for Backend authentication.</param>
     /// <returns>A task that represents the asynchronous operation. The task result contains the created in-app wallet.</returns>
     /// <exception cref="ArgumentException">Thrown when required parameters are not provided.</exception>
     public static async Task<EcosystemWallet> Create(
@@ -86,7 +90,8 @@ public static async Task<EcosystemWallet> Create(
         AuthProvider authProvider = Thirdweb.AuthProvider.Default,
         string storageDirectoryPath = null,
         IThirdwebWallet siweSigner = null,
-        string legacyEncryptionKey = null
+        string legacyEncryptionKey = null,
+        string walletSecret = null
     )
     {
         if (client == null)
@@ -117,6 +122,7 @@ public static async Task<EcosystemWallet> Create(
             Thirdweb.AuthProvider.Github => "Github",
             Thirdweb.AuthProvider.Twitch => "Twitch",
             Thirdweb.AuthProvider.Steam => "Steam",
+            Thirdweb.AuthProvider.Backend => "Backend",
             Thirdweb.AuthProvider.Default => string.IsNullOrEmpty(email) ? "Phone" : "Email",
             _ => throw new ArgumentException("Invalid AuthProvider"),
         };
@@ -150,7 +156,7 @@ public static async Task<EcosystemWallet> Create(
         try
         {
             var userAddress = await ResumeEnclaveSession(enclaveHttpClient, embeddedWallet, email, phoneNumber, authproviderStr).ConfigureAwait(false);
-            return new EcosystemWallet(ecosystemId, ecosystemPartnerId, client, embeddedWallet, enclaveHttpClient, email, phoneNumber, authproviderStr, siweSigner, legacyEncryptionKey)
+            return new EcosystemWallet(ecosystemId, ecosystemPartnerId, client, embeddedWallet, enclaveHttpClient, email, phoneNumber, authproviderStr, siweSigner, legacyEncryptionKey, walletSecret)
             {
                 Address = userAddress
             };
@@ -158,7 +164,7 @@ public static async Task<EcosystemWallet> Create(
         catch
         {
             enclaveHttpClient.RemoveHeader("Authorization");
-            return new EcosystemWallet(ecosystemId, ecosystemPartnerId, client, embeddedWallet, enclaveHttpClient, email, phoneNumber, authproviderStr, siweSigner, legacyEncryptionKey)
+            return new EcosystemWallet(ecosystemId, ecosystemPartnerId, client, embeddedWallet, enclaveHttpClient, email, phoneNumber, authproviderStr, siweSigner, legacyEncryptionKey, walletSecret)
             {
                 Address = null
             };
@@ -468,6 +474,13 @@ public async Task<List<LinkedAccount>> LinkAccount(
                 }
                 serverRes = await ecosystemWallet.PreAuth_Siwe(ecosystemWallet.SiweSigner, chainId.Value).ConfigureAwait(false);
                 break;
+            case "Backend":
+                if (string.IsNullOrEmpty(ecosystemWallet.WalletSecret))
+                {
+                    throw new ArgumentException("Cannot link account with a Backend wallet without a wallet secret.");
+                }
+                serverRes = await ecosystemWallet.PreAuth_Backend(ecosystemWallet.WalletSecret).ConfigureAwait(false);
+                break;
             case "JWT":
                 if (string.IsNullOrEmpty(jwt))
                 {
@@ -692,12 +705,12 @@ public async Task<string> LoginWithOauth(
 
     private async Task<Server.VerifyResult> PreAuth_Siwe(IThirdwebWallet siweSigner, BigInteger chainId)
     {
-        if (this.SiweSigner == null)
+        if (siweSigner == null)
         {
             throw new ArgumentNullException(nameof(siweSigner), "SIWE Signer wallet cannot be null.");
         }
 
-        if (!await this.SiweSigner.IsConnected().ConfigureAwait(false))
+        if (!await siweSigner.IsConnected().ConfigureAwait(false))
         {
             throw new InvalidOperationException("SIWE Signer wallet must be connected as this operation requires it to sign a message.");
         }
@@ -716,6 +729,23 @@ public async Task<string> LoginWithSiwe(BigInteger chainId)
 
     #endregion
 
+    #region Backend
+
+    private async Task<Server.VerifyResult> PreAuth_Backend(string walletSecret)
+    {
+        return string.IsNullOrEmpty(walletSecret)
+            ? throw new ArgumentException("Wallet secret cannot be null or empty.", nameof(walletSecret))
+            : await this.EmbeddedWallet.SignInWithBackendAsync(walletSecret).ConfigureAwait(false);
+    }
+
+    public async Task<string> LoginWithBackend()
+    {
+        var serverRes = await this.PreAuth_Backend(this.WalletSecret).ConfigureAwait(false);
+        return await this.PostAuth(serverRes).ConfigureAwait(false);
+    }
+
+    #endregion
+
     #region Guest
 
     private async Task<Server.VerifyResult> PreAuth_Guest()
@@ -746,13 +776,12 @@ public async Task<string> LoginWithGuest()
 
     private async Task<Server.VerifyResult> PreAuth_JWT(string jwt)
     {
-        return string.IsNullOrEmpty(jwt) ? throw new ArgumentException(nameof(jwt), "JWT cannot be null or empty.") : await this.EmbeddedWallet.SignInWithJwtAsync(jwt).ConfigureAwait(false);
+        return string.IsNullOrEmpty(jwt) ? throw new ArgumentException("JWT cannot be null or empty.", nameof(jwt)) : await this.EmbeddedWallet.SignInWithJwtAsync(jwt).ConfigureAwait(false);
     }
 
     public async Task<string> LoginWithJWT(string jwt)
     {
-        var serverRes = string.IsNullOrEmpty(jwt) ? throw new ArgumentException("JWT cannot be null or empty.", nameof(jwt)) : await this.EmbeddedWallet.SignInWithJwtAsync(jwt).ConfigureAwait(false);
-
+        var serverRes = await this.PreAuth_JWT(jwt).ConfigureAwait(false);
         return await this.PostAuth(serverRes).ConfigureAwait(false);
     }
 
diff --git a/Thirdweb/Thirdweb.Wallets/InAppWallet/EmbeddedWallet.Authentication/Server.cs b/Thirdweb/Thirdweb.Wallets/InAppWallet/EmbeddedWallet.Authentication/Server.cs
index a396ff1..f4743fe 100644
--- a/Thirdweb/Thirdweb.Wallets/InAppWallet/EmbeddedWallet.Authentication/Server.cs
+++ b/Thirdweb/Thirdweb.Wallets/InAppWallet/EmbeddedWallet.Authentication/Server.cs
@@ -16,6 +16,8 @@ internal abstract class ServerBase
     internal abstract Task<LoginPayloadData> FetchSiwePayloadAsync(string address, string chainId);
     internal abstract Task<Server.VerifyResult> VerifySiweAsync(LoginPayloadData payload, string signature);
 
+    internal abstract Task<Server.VerifyResult> VerifyBackendAsync(string walletSecret);
+
     internal abstract Task<Server.VerifyResult> VerifyGuestAsync(string sessionId);
 
     internal abstract Task<string> SendEmailOtpAsync(string emailAddress);
@@ -155,8 +157,19 @@ internal override async Task<VerifyResult> VerifySiweAsync(LoginPayloadData payl
         return await this.InvokeAuthResultLambdaAsync(authResult).ConfigureAwait(false);
     }
 
-    // login/guest
+    // login/backend
+    internal override async Task<VerifyResult> VerifyBackendAsync(string walletSecret)
+    {
+        var uri = MakeUri2024("/login/backend");
+        var content = MakeHttpContent(new { walletSecret });
+        var response = await this._httpClient.PostAsync(uri.ToString(), content).ConfigureAwait(false);
+        await CheckStatusCodeAsync(response).ConfigureAwait(false);
 
+        var authResult = await DeserializeAsync<AuthResultType>(response).ConfigureAwait(false);
+        return await this.InvokeAuthResultLambdaAsync(authResult).ConfigureAwait(false);
+    }
+
+    // login/guest
     internal override async Task<VerifyResult> VerifyGuestAsync(string sessionId)
     {
         var uri = MakeUri2024("/login/guest/callback");
diff --git a/Thirdweb/Thirdweb.Wallets/InAppWallet/EmbeddedWallet/EmbeddedWallet.Backend.cs b/Thirdweb/Thirdweb.Wallets/InAppWallet/EmbeddedWallet/EmbeddedWallet.Backend.cs
new file mode 100644
index 0000000..d31e1cd
--- /dev/null
+++ b/Thirdweb/Thirdweb.Wallets/InAppWallet/EmbeddedWallet/EmbeddedWallet.Backend.cs
@@ -0,0 +1,9 @@
+namespace Thirdweb.EWS;
+
+internal partial class EmbeddedWallet
+{
+    public async Task<Server.VerifyResult> SignInWithBackendAsync(string walletSecret)
+    {
+        return await this._server.VerifyBackendAsync(walletSecret).ConfigureAwait(false);
+    }
+}
diff --git a/Thirdweb/Thirdweb.Wallets/InAppWallet/InAppWallet.Types.cs b/Thirdweb/Thirdweb.Wallets/InAppWallet/InAppWallet.Types.cs
index 061e788..76d45d9 100644
--- a/Thirdweb/Thirdweb.Wallets/InAppWallet/InAppWallet.Types.cs
+++ b/Thirdweb/Thirdweb.Wallets/InAppWallet/InAppWallet.Types.cs
@@ -23,7 +23,8 @@ public enum AuthProvider
     Coinbase,
     Github,
     Twitch,
-    Steam
+    Steam,
+    Backend
 }
 
 /// <summary>
diff --git a/Thirdweb/Thirdweb.Wallets/InAppWallet/InAppWallet.cs b/Thirdweb/Thirdweb.Wallets/InAppWallet/InAppWallet.cs
index 8a7f8b8..168db0f 100644
--- a/Thirdweb/Thirdweb.Wallets/InAppWallet/InAppWallet.cs
+++ b/Thirdweb/Thirdweb.Wallets/InAppWallet/InAppWallet.cs
@@ -16,9 +16,10 @@ internal InAppWallet(
         string authProvider,
         IThirdwebWallet siweSigner,
         string address,
-        string legacyEncryptionKey
+        string legacyEncryptionKey,
+        string walletSecret
     )
-        : base(null, null, client, embeddedWallet, httpClient, email, phoneNumber, authProvider, siweSigner, legacyEncryptionKey)
+        : base(null, null, client, embeddedWallet, httpClient, email, phoneNumber, authProvider, siweSigner, legacyEncryptionKey, walletSecret)
     {
         this.Address = address;
     }
@@ -33,6 +34,7 @@ string legacyEncryptionKey
     /// <param name="storageDirectoryPath">The path to the storage directory.</param>
     /// <param name="siweSigner">The SIWE signer wallet for SIWE authentication.</param>
     /// <param name="legacyEncryptionKey">The encryption key that is no longer required but was used in the past. Only pass this if you had used custom auth before this was deprecated.</param>
+    /// <param name="walletSecret">The wallet secret for backend authentication.</param>
     /// <returns>A task that represents the asynchronous operation. The task result contains the created in-app wallet.</returns>
     /// <exception cref="ArgumentException">Thrown when required parameters are not provided.</exception>
     public static async Task<InAppWallet> Create(
@@ -42,11 +44,12 @@ public static async Task<InAppWallet> Create(
         AuthProvider authProvider = Thirdweb.AuthProvider.Default,
         string storageDirectoryPath = null,
         IThirdwebWallet siweSigner = null,
-        string legacyEncryptionKey = null
+        string legacyEncryptionKey = null,
+        string walletSecret = null
     )
     {
         storageDirectoryPath ??= Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "Thirdweb", "InAppWallet");
-        var ecoWallet = await Create(client, null, null, email, phoneNumber, authProvider, storageDirectoryPath, siweSigner, legacyEncryptionKey);
+        var ecoWallet = await Create(client, null, null, email, phoneNumber, authProvider, storageDirectoryPath, siweSigner, legacyEncryptionKey, walletSecret);
         return new InAppWallet(
             ecoWallet.Client,
             ecoWallet.EmbeddedWallet,
@@ -56,7 +59,8 @@ public static async Task<InAppWallet> Create(
             ecoWallet.AuthProvider,
             ecoWallet.SiweSigner,
             ecoWallet.Address,
-            ecoWallet.LegacyEncryptionKey
+            ecoWallet.LegacyEncryptionKey,
+            ecoWallet.WalletSecret
         );
     }
 }