diff --git a/clap/dplug/clap/client.d b/clap/dplug/clap/client.d
index e70924c0..32455228 100644
--- a/clap/dplug/clap/client.d
+++ b/clap/dplug/clap/client.d
@@ -1050,6 +1050,7 @@ nothrow @nogc:
     this(const(clap_host_t)* host)
     {
         _host = host;
+        _host_gui = cast(clap_host_gui_t*) host.get_extension(host, "clap.gui".ptr);
     }
 
     /// Notifies the host that editing of a parameter has begun from UI side.
@@ -1082,8 +1083,11 @@ nothrow @nogc:
     /// Returns: `true` if the host parent window has been resized.
     override bool requestResize(int widthLogicalPixels, int heightLogicalPixels)
     {
-        // TODO
-        return false;
+        if (!_host_gui)
+            return false;
+        if (widthLogicalPixels < 0 || heightLogicalPixels < 0)
+            return false;
+        return _host_gui.request_resize(_host, widthLogicalPixels, heightLogicalPixels);
     }
 
     override bool notifyResized()
@@ -1112,5 +1116,6 @@ nothrow @nogc:
     }
 
     const(clap_host_t)* _host;
+    const(clap_host_gui_t)* _host_gui;
 }
 
diff --git a/clap/dplug/clap/types.d b/clap/dplug/clap/types.d
index 777e94ae..459fc400 100644
--- a/clap/dplug/clap/types.d
+++ b/clap/dplug/clap/types.d
@@ -1216,6 +1216,8 @@ extern(C) nothrow @nogc:
 
 struct clap_host_gui_t 
 {
+extern(C) nothrow @nogc:
+
     // The host should call get_resize_hints() again.
     // [thread-safe & !floating]
     void function(const clap_host_t *host) resize_hints_changed; 
@@ -1252,6 +1254,7 @@ struct clap_host_gui_t
 
 struct clap_host_t 
 {
+extern(C) nothrow @nogc:
     clap_version_t clap_version; // initialized to CLAP_VERSION
 
     void* host_data; // reserved pointer for the host