diff --git a/src/base/arena.h b/src/base/arena.h
index 0147dd4..c77c2f8 100644
--- a/src/base/arena.h
+++ b/src/base/arena.h
@@ -80,7 +80,8 @@ static INLINE void *arena_allocator_func(Allocator *allocator, AllocOperation op
         case Alloc_Op_Aligned:
             return arena_push(allocator->data, size, align);
 
-        case Alloc_Op_Free: // can't free from  an marena
+        case Alloc_Op_Free: // can't free from  an arena
+            NotImplemented;
             return NULL;
 
         case Alloc_Op_Free_All:
diff --git a/src/base/marena.h b/src/base/marena.h
index bd48b8e..1399770 100644
--- a/src/base/marena.h
+++ b/src/base/marena.h
@@ -102,6 +102,7 @@ static INLINE void *marena_allocator_func(Allocator *allocator, AllocOperation o
             return marena_push_aligned(allocator->data, size, align);
 
         case Alloc_Op_Free: // can't free/Free_all from  an marena
+            NotImplemented;
             return NULL;
 
         case Alloc_Op_Free_All:
diff --git a/src/base/platform.c b/src/base/platform.c
index fa5a2b7..fcff7a4 100644
--- a/src/base/platform.c
+++ b/src/base/platform.c
@@ -30,7 +30,7 @@ static void *platform_allocator_func(Allocator *allocator, AllocOperation operat
         case Alloc_Op_Aligned:
             return aligned_alloc(size, align);
 
-        case Alloc_Op_Free: // can't free/Free_all from  an marena
+        case Alloc_Op_Free:
             free(memory);
             return NULL;