diff --git a/src/i_logos_execution_zone_wallet_module.h b/src/i_logos_execution_zone_wallet_module.h
index 95b48a8..94dcc11 100644
--- a/src/i_logos_execution_zone_wallet_module.h
+++ b/src/i_logos_execution_zone_wallet_module.h
@@ -90,7 +90,7 @@ public:
 
     virtual QList<uint32_t> serialization_helper(const QList<uint8_t>& input_data) = 0;
 
-    virtual QString authenticated_transfer_elf(QList<uint8_t>& output) = 0;
+    virtual QByteArray authenticated_transfer_elf() = 0;
     virtual QList<uint8_t> token_elf() = 0;
     virtual QList<uint8_t> amm_elf() = 0;
     virtual QList<uint8_t> ata_elf() = 0;
diff --git a/src/logos_execution_zone_wallet_module.cpp b/src/logos_execution_zone_wallet_module.cpp
index 288272b..7675c35 100644
--- a/src/logos_execution_zone_wallet_module.cpp
+++ b/src/logos_execution_zone_wallet_module.cpp
@@ -802,19 +802,19 @@ QList<uint8_t> LogosExecutionZoneWalletModule::ata_elf() {
     return result;
 }
 
-QString LogosExecutionZoneWalletModule::authenticated_transfer_elf(QList<uint8_t>& output) {
+QByteArray LogosExecutionZoneWalletModule::authenticated_transfer_elf() {
     FfiProgram ffi_program {};
     WalletFfiError error = wallet_ffi_transfer_elf(&ffi_program);
     if (error != SUCCESS) {
-        return QString("authenticated_transfer_elf: wallet FFI error %1").arg(error);
+        qWarning() << "authenticated_transfer_elf: wallet FFI error " << error;
+        return QByteArray();
     }
 
-    output = QList<uint8_t>(ffi_program.elf_data, ffi_program.elf_data + ffi_program.elf_size);
+    QByteArray result(reinterpret_cast<const char*>(ffi_program.elf_data), ffi_program.elf_size);
     wallet_ffi_free_ffi_program(&ffi_program);
-    return QString();
+    return result;
 }
 
-
 QString LogosExecutionZoneWalletModule::send_generic_public_transaction(
         const QList<QString>& account_ids,
         const QList<bool>& signing_requirements, 
diff --git a/src/logos_execution_zone_wallet_module.h b/src/logos_execution_zone_wallet_module.h
index 31da572..d036ed4 100644
--- a/src/logos_execution_zone_wallet_module.h
+++ b/src/logos_execution_zone_wallet_module.h
@@ -118,7 +118,7 @@ public:
 
     Q_INVOKABLE QList<uint32_t> serialization_helper(const QList<uint8_t>& input_data) override;
 
-    Q_INVOKABLE QString authenticated_transfer_elf(QList<uint8_t>& output) override;
+    Q_INVOKABLE QByteArray authenticated_transfer_elf() override;
     Q_INVOKABLE QList<uint8_t> token_elf() override;
     Q_INVOKABLE QList<uint8_t> amm_elf() override;
     Q_INVOKABLE QList<uint8_t> ata_elf() override;