diff --git a/extras/fixture/src/unity_fixture.c b/extras/fixture/src/unity_fixture.c
index 575f9e9..01d3ae6 100644
--- a/extras/fixture/src/unity_fixture.c
+++ b/extras/fixture/src/unity_fixture.c
@@ -196,7 +196,7 @@ void * unity_malloc(size_t size)
 
     malloc_count++;
 
-    guard = (Guard*)malloc(size + sizeof(Guard) + 4);
+    guard = (Guard*)UNITY_FIXTURE_MALLOC(size + sizeof(Guard) + 4);
     guard->size = size;
     mem = (char*)&(guard[1]);
     memcpy(&mem[size], end, strlen(end) + 1);
@@ -219,7 +219,7 @@ static void release_memory(void * mem)
     guard--;
 
     malloc_count--;
-    free(guard);
+    UNITY_FIXTURE_FREE(guard);
 }
 
 void unity_free(void * mem)
diff --git a/extras/fixture/src/unity_fixture_malloc_overrides.h b/extras/fixture/src/unity_fixture_malloc_overrides.h
index a19c1ea..27b9884 100644
--- a/extras/fixture/src/unity_fixture_malloc_overrides.h
+++ b/extras/fixture/src/unity_fixture_malloc_overrides.h
@@ -10,6 +10,28 @@
 
 #include <stddef.h>
 
+// This function is used by the Unity Fixture to allocate memory on
+// the heap and can be overridden with platform-specific heap
+// implementations. For example, when using FreeRTOS
+// UNITY_FIXTURE_MALLOC becomes pvPortMalloc().
+
+#ifndef UNITY_FIXTURE_MALLOC
+   #define UNITY_FIXTURE_MALLOC( SIZE ) malloc( ( SIZE ) )
+#else
+   extern void * UNITY_FIXTURE_MALLOC(size_t size);
+#endif
+
+// This function is used by the Unity Fixture to release memory in the
+// heap and can be overridden with platform-specific heap
+// implementations. For example, when using FreeRTOS
+// UNITY_FIXTURE_FREE becomes vPortFree().
+
+#ifndef UNITY_FIXTURE_FREE
+   #define UNITY_FIXTURE_FREE( PTR ) free( ( PTR ) )
+#else
+   extern void UNITY_FIXTURE_FREE(void *ptr);
+#endif
+
 #define malloc  unity_malloc
 #define calloc  unity_calloc
 #define realloc unity_realloc