diff --git a/modules/client/login.cc b/modules/client/login.cc
index 7e9c9548f..668775a94 100644
--- a/modules/client/login.cc
+++ b/modules/client/login.cc
@@ -112,7 +112,7 @@ post__login_password(client &client,
 		unquote(json::get<"device_id"_>(request))
 	};
 
-	const m::id::device device_id
+	const auto device_id
 	{
 		requested_device_id?
 			m::id::device::buf{requested_device_id, my_host()}:
diff --git a/modules/client/register.cc b/modules/client/register.cc
index b84510613..4f8559941 100644
--- a/modules/client/register.cc
+++ b/modules/client/register.cc
@@ -97,7 +97,7 @@ try
 		unquote(json::get<"device_id"_>(request))
 	};
 
-	const m::id::device device_id
+	const auto device_id
 	{
 		requested_device_id?
 			m::id::device::buf{requested_device_id, my_host()}: