diff --git a/src/genkey.c b/src/genkey.c
index 04de2ba..d2d4c53 100644
--- a/src/genkey.c
+++ b/src/genkey.c
@@ -14,8 +14,14 @@
 #include <sys/syscall.h>
 #endif
 #ifdef __APPLE__
+#include <AvailabilityMacros.h>
+#ifndef MAC_OS_X_VERSION_10_12
+#define MAC_OS_X_VERSION_10_12 101200
+#endif
+#if MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_12
 #include <sys/random.h>
 #endif
+#endif
 
 #include "curve25519.h"
 #include "encoding.h"
@@ -26,7 +32,7 @@ static inline ssize_t get_random_bytes(uint8_t *out, size_t len)
 	ssize_t ret;
 	int fd;
 
-#if defined(__OpenBSD__) || defined(__APPLE__) || (defined(__GLIBC__) && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 25)))
+#if defined(__OpenBSD__) || (defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_12) || (defined(__GLIBC__) && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 25)))
 	ret = getentropy(out, len);
 	if (!ret)
 		return len;