diff --git a/Romulus-M/encrypt_wrapper.c b/Romulus-M/encrypt_wrapper.c
index 275b40b..0737e4a 100644
--- a/Romulus-M/encrypt_wrapper.c
+++ b/Romulus-M/encrypt_wrapper.c
@@ -5,6 +5,11 @@
 #ifdef _MSC_VER
 #define __bswap_16 _byteswap_ushort
 #define __bswap_32 _byteswap_ulong
+#elif __APPLE__
+#include <libkern/OSByteOrder.h>
+#define __bswap_16 OSSwapInt16
+#define __bswap_32 OSSwapInt32
+#define __bswap_64 OSSwapInt64
 #else
 #include <byteswap.h>
 #endif
@@ -163,4 +168,4 @@ void fill_random(unsigned char* buffer, int length){
         secRandom = rand(&rCtx);
         memcpy(&buffer[i], &secRandom, MIN(sizeof(UINT32), length-i));
     }
-}
\ No newline at end of file
+}