diff --git a/engine/core/src/engine.cpp b/engine/core/src/engine.cpp
index 7a593a1..266060d 100755
--- a/engine/core/src/engine.cpp
+++ b/engine/core/src/engine.cpp
@@ -84,7 +84,7 @@ void engine::set_app(prism::app* p_app) {
 
     this->current_app = p_app;
 
-    if(platform::supports_feature(PlatformFeature::Windowing) && ::engine->get_app()->is_multimodal()) {
+    if(platform::supports_feature(PlatformFeature::Windowing) && get_app()->is_multimodal()) {
         ImGui::GetIO().ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;
     }
 
@@ -427,7 +427,7 @@ void engine::add_window(void* native_handle, const platform::window_ptr window_p
         current_renderer = std::make_unique<prism::renderer>(gfx);
 
         ImGuiViewport* main_viewport = ImGui::GetMainViewport();
-        main_viewport->PlatformHandle = ::engine->get_main_window();
+        main_viewport->PlatformHandle = get_main_window();
     }
 
     const auto drawable_extent = platform::get_window_drawable_size(window_ptr);
diff --git a/engine/gfx/dx12/src/gfx_dx12.cpp b/engine/gfx/dx12/src/gfx_dx12.cpp
index 5b54f8e..e2f02d0 100755
--- a/engine/gfx/dx12/src/gfx_dx12.cpp
+++ b/engine/gfx/dx12/src/gfx_dx12.cpp
@@ -5,6 +5,7 @@
 #include <d3dcompiler.h>
 
 #include <wrl.h>
+#include <codecvt>
 
 // from https://stackoverflow.com/a/18374698
 std::string ws2s(const std::wstring& wstr) {
diff --git a/platforms/sdl/main.cpp.in b/platforms/sdl/main.cpp.in
index 8cc7173..8d2713d 100644
--- a/platforms/sdl/main.cpp.in
+++ b/platforms/sdl/main.cpp.in
@@ -34,7 +34,7 @@ std::vector<SDL_Window*> windows;
 std::map<SDL_Window*, SDL_Renderer*> renderers;
 SDL_Window* main_window = nullptr;
 
-SDL_Window* get_window(const platform::window_ptr index) {
+extern "C" SDL_Window* get_window(const platform::window_ptr index) {
     for(auto& window : windows) {
         if(window == index)
             return window;
diff --git a/platforms/sdl/sdl_metal.mm b/platforms/sdl/sdl_metal.mm
index 85dc2f5..732128e 100644
--- a/platforms/sdl/sdl_metal.mm
+++ b/platforms/sdl/sdl_metal.mm
@@ -10,7 +10,7 @@
 extern std::vector<SDL_Window*> windows;
 extern std::map<SDL_Window*, SDL_Renderer*> renderers;
 
-SDL_Window* get_window(platform::window_ptr index);
+extern "C" SDL_Window* get_window(platform::window_ptr index);
 CAMetalLayer* get_layer(platform::window_ptr index) {
     return (__bridge CAMetalLayer*)SDL_RenderGetMetalLayer(renderers[get_window(index)]);
 }
diff --git a/platforms/sdl/sdl_vulkan.cpp b/platforms/sdl/sdl_vulkan.cpp
index 0a6f6e1..0a3208f 100644
--- a/platforms/sdl/sdl_vulkan.cpp
+++ b/platforms/sdl/sdl_vulkan.cpp
@@ -5,7 +5,7 @@
 
 extern std::vector<SDL_Window*> windows;
 
-SDL_Window* get_window(platform::window_ptr index);
+extern "C" SDL_Window* get_window(platform::window_ptr index);
 
 void* create_vulkan_surface(platform::window_ptr window, void* surface_creation_info) {
     auto vulkan_surface_info = (vulkan_surface_creation_info*)surface_creation_info;