diff --git a/src/io/dataBuffer.h b/src/io/dataBuffer.h
index 23d0d28..c70c9c4 100644
--- a/src/io/dataBuffer.h
+++ b/src/io/dataBuffer.h
@@ -106,6 +106,13 @@ class DataBuffer
         writeVLQu64(i);
     }
 
+#ifdef __MACOS__
+    void write(size_t& i)
+    {
+        writeVLQu64(i);
+    }
+#endif
+
     void write(const float f)
     {
         appendRaw(&f, sizeof(f));