diff --git a/Examples/Mandelbrot/main.cpp b/Examples/Mandelbrot/main.cpp
index aee0f80..064058a 100644
--- a/Examples/Mandelbrot/main.cpp
+++ b/Examples/Mandelbrot/main.cpp
@@ -1,5 +1,6 @@
 #define _CRT_SECURE_NO_WARNINGS // for STB
 
+#define THIRTEEN_IMPLEMENTATION
 #include "../../thirteen.h"
 
 #include <stdio.h>
diff --git a/Examples/Minesweeper/main.cpp b/Examples/Minesweeper/main.cpp
index be78e79..c733601 100644
--- a/Examples/Minesweeper/main.cpp
+++ b/Examples/Minesweeper/main.cpp
@@ -1,5 +1,6 @@
 #define _CRT_SECURE_NO_WARNINGS // for STB
 
+#define THIRTEEN_IMPLEMENTATION
 #include "../../thirteen.h"
 
 #include <stdio.h>
diff --git a/Examples/Simple/main.cpp b/Examples/Simple/main.cpp
index 59d2d9c..69b966f 100644
--- a/Examples/Simple/main.cpp
+++ b/Examples/Simple/main.cpp
@@ -1,5 +1,6 @@
 #define _CRT_SECURE_NO_WARNINGS // for STB
 
+#define THIRTEEN_IMPLEMENTATION
 #include "../../thirteen.h"
 
 #include <stdio.h>
diff --git a/thirteen.h b/thirteen.h
index 3e54d94..03a60fd 100644
--- a/thirteen.h
+++ b/thirteen.h
@@ -164,7 +164,7 @@ namespace Thirteen
 }
 
 // ========== Implementation ==========
-
+#ifdef THIRTEEN_IMPLEMENTATION
 namespace Thirteen
 {
 
@@ -2351,3 +2351,4 @@ namespace Thirteen
         Internal::Pixels = nullptr;
     }
 }
+#endif // THIRTEEN_IMPLEMENTATION