diff --git a/win_directx_helper/CMakeLists.txt b/win_directx_helper/CMakeLists.txt
index 19ade2c..889f8a9 100644
--- a/win_directx_helper/CMakeLists.txt
+++ b/win_directx_helper/CMakeLists.txt
@@ -14,3 +14,8 @@ PRIVATE
 )
 
 validate_d3d_compiler(win_directx_helper)
+
+target_link_libraries(win_directx_helper
+PUBLIC
+    desktop-app::external_openssl
+)
diff --git a/win_directx_helper/win_directx_helper.cpp b/win_directx_helper/win_directx_helper.cpp
index 481497b..13a90f0 100644
--- a/win_directx_helper/win_directx_helper.cpp
+++ b/win_directx_helper/win_directx_helper.cpp
@@ -8,7 +8,9 @@
 #include <d3d9.h>
 #include <d3d11.h>
 #include <d3dcompiler.h>
+extern "C" {
 #include <openssl/sha.h>
+} // extern "C"
 #include <string>
 #include <vector>
 #include <array>