diff --git a/src/aes.c b/src/aes.c
index 3fbea53..2d4ec03 100644
--- a/src/aes.c
+++ b/src/aes.c
@@ -17,12 +17,12 @@
  */
 
 
-#include <endian.h>  // for be32toh, htobe32
 #include <stdint.h>  // for uint32_t, uint8_t
 #include <stdlib.h>  // for calloc, free
 #include <string.h>  // for memcpy, size_t
 #include "aes.h"     // for AES_BLOCK_SIZE, aes_context_t, AES128_KEY_BYTES
 #include "n2n.h"     // for TRACE_ERROR, traceEvent
+#include "portable_endian.h"  // for be32toh, htobe32
 
 
 #if defined (HAVE_OPENSSL_1_1) // openSSL 1.1 ---------------------------------------------------------------------