diff --git a/minimal_heap.h b/minimal_heap.h
index cf87117..f1d10f6 100644
--- a/minimal_heap.h
+++ b/minimal_heap.h
@@ -21,8 +21,10 @@
 #endif
 /* */
 
-typedef void*(MIHP_PlatformRequestMemoryFn)(const struct _MIHP_Heap* heap, size_t minRequestedSize, size_t* outActualSize);
-typedef bool (MIHP_PlatformFreeMemoryFn)(const struct _MIHP_Heap* heap, void* ptr, size_t actualSize);
+typedef uintptr_t MIHP_HeapOpaque;
+
+typedef void*(MIHP_PlatformRequestMemoryFn)(MIHP_HeapOpaque heap, size_t minRequestedSize, size_t* outActualSize);
+typedef bool (MIHP_PlatformFreeMemoryFn)(MIHP_HeapOpaque heap, void* ptr, size_t actualSize);
 
 typedef enum _MIHP_HEAP_CORRUPTION_ERROR
 {
@@ -33,8 +35,8 @@ typedef enum _MIHP_HEAP_CORRUPTION_ERROR
 
 typedef void (MIHP_OnHeapCorruptionDetectedFn)(const struct _MIHP_Heap* heap, struct _MIHP_HeapCorruptionInfo corruptionInfo);
 
-typedef void(MIHP_LockHeapFn)(const struct _MIHP_Heap* heap, void* heapLock);
-typedef void(MIHP_UnlockHeapFn)(const struct _MIHP_Heap* heap, void* heapLock);
+typedef void(MIHP_LockHeapFn)(MIHP_HeapOpaque heap, void* heapLock);
+typedef void(MIHP_UnlockHeapFn)(MIHP_HeapOpaque heap, void* heapLock);
 
 typedef enum _MIHP_HeapValidationMode
 {
@@ -87,7 +89,7 @@ typedef struct _MIHP_HeapMemoryAreaHeader
 	struct _MIHP_HeapSegmentHeader*		LastSuccessfulAllocationSegment;
 
 	// TODO: Change this to an InstigatingHeapUuid (opaque ptr)
-	const struct _MIHP_Heap*			InstigatingHeap; // Heap that created this area. May not always be the owning heap (in case of a merge) or safe to deference!
+	MIHP_HeapOpaque		InstigatingHeap; // Heap that created this area.
 
 	uint32_t 			Checksum; // Checksum must be the last member !
 } MIHP_HeapMemoryAreaHeader;
diff --git a/minimal_heap_implementation.inl b/minimal_heap_implementation.inl
index 1372f42..3b22d59 100644
--- a/minimal_heap_implementation.inl
+++ b/minimal_heap_implementation.inl
@@ -571,13 +571,13 @@ bool MIHP_WalkHeap(MIHP_Heap* heap, MIHP_WalkHeapCallbackFn* callback)
 void MIHP_LockHeap(MIHP_Heap* heap)
 {
 	if (heap->Config.HeapLock)
-		heap->Config.LockHeapFn(heap, heap->Config.HeapLock);
+		heap->Config.LockHeapFn((MIHP_HeapOpaque)heap, heap->Config.HeapLock);
 }
 
 void MIHP_UnlockHeap(MIHP_Heap* heap)
 {
 	if (heap->Config.HeapLock)
-		heap->Config.UnlockHeapFn(heap, heap->Config.HeapLock);
+		heap->Config.UnlockHeapFn((MIHP_HeapOpaque)heap, heap->Config.HeapLock);
 }
 
 MIHP_HeapMemoryAreaHeader* MIHP_CreateHeapMemoryArea(MIHP_Heap* heap, size_t requestedSize)
@@ -592,14 +592,14 @@ MIHP_HeapMemoryAreaHeader* MIHP_CreateHeapMemoryArea(MIHP_Heap* heap, size_t req
 		return NULL;
 
 	size_t actualSize = 0;
-	MIHP_HeapMemoryAreaHeader* area = (MIHP_HeapMemoryAreaHeader*)heap->Config.PlatformRequestMemoryFn(heap, effectiveSize, &actualSize);
+	MIHP_HeapMemoryAreaHeader* area = (MIHP_HeapMemoryAreaHeader*)heap->Config.PlatformRequestMemoryFn((MIHP_HeapOpaque)heap, effectiveSize, &actualSize);
 	if (area == NULL)
 		return NULL;
 
 	MIHP_ASSERT(actualSize >= effectiveSize);
 	MIHP_MEMSET(area, sizeof(MIHP_HeapMemoryAreaHeader), 0);
 
-	area->InstigatingHeap = heap;
+	area->InstigatingHeap = (MIHP_HeapOpaque)heap;
 	area->AreaSize = actualSize;
 	area->Checksum = ~0;
 
diff --git a/minimal_heap_test.c b/minimal_heap_test.cpp
similarity index 94%
rename from minimal_heap_test.c
rename to minimal_heap_test.cpp
index fb42496..7f57335 100644
--- a/minimal_heap_test.c
+++ b/minimal_heap_test.cpp
@@ -12,13 +12,13 @@
 
 #define MIHP_ValidateHeap(x)
 
-void* RequestMemory(const MIHP_Heap* heap, size_t minRequestedSize, size_t* outActualSize)
+void* RequestMemory(MIHP_HeapOpaque heap, size_t minRequestedSize, size_t* outActualSize)
 {
 	*outActualSize = minRequestedSize;
 	return malloc(minRequestedSize);
 }
 
-bool FreeMemory(const MIHP_Heap* heap, void* ptr, size_t actualSize)
+bool FreeMemory(MIHP_HeapOpaque heap, void* ptr, size_t actualSize)
 {
 	free(ptr);
 	return true;
diff --git a/minimal_heap_test.vcxproj b/minimal_heap_test.vcxproj
index 06693a7..92a73e8 100644
--- a/minimal_heap_test.vcxproj
+++ b/minimal_heap_test.vcxproj
@@ -124,7 +124,7 @@
     </Link>
   </ItemDefinitionGroup>
   <ItemGroup>
-    <ClCompile Include="minimal_heap_test.c" />
+    <ClCompile Include="minimal_heap_test.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="minimal_heap.h" />
diff --git a/minimal_heap_test.vcxproj.filters b/minimal_heap_test.vcxproj.filters
index aad3cae..b1b7f20 100644
--- a/minimal_heap_test.vcxproj.filters
+++ b/minimal_heap_test.vcxproj.filters
@@ -15,7 +15,7 @@
     </Filter>
   </ItemGroup>
   <ItemGroup>
-    <ClCompile Include="minimal_heap_test.c">
+    <ClCompile Include="minimal_heap_test.cpp">
       <Filter>Quelldateien</Filter>
     </ClCompile>
   </ItemGroup>