diff --git a/include/Makefile.am b/include/Makefile.am
index 30423c4..b40ac03 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -1,6 +1,7 @@
 noinst_HEADERS =
 noinst_HEADERS += signal.h
 noinst_HEADERS += unistd.h
+noinst_HEADERS += machine/endian.h
 noinst_HEADERS += sys/cdefs.h
 noinst_HEADERS += sys/queue.h
 noinst_HEADERS += sys/socket.h
diff --git a/include/machine/endian.h b/include/machine/endian.h
new file mode 100644
index 0000000..5ec39af
--- /dev/null
+++ b/include/machine/endian.h
@@ -0,0 +1,40 @@
+/*
+ * Public domain
+ * machine/endian.h compatibility shim
+ */
+
+#ifndef LIBCRYPTOCOMPAT_BYTE_ORDER_H_
+#define LIBCRYPTOCOMPAT_BYTE_ORDER_H_
+
+#if defined(_WIN32)
+
+#define LITTLE_ENDIAN  1234
+#define BIG_ENDIAN 4321
+#define PDP_ENDIAN	3412
+
+/*
+ * Use GCC and Visual Studio compiler defines to determine endian.
+ */
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#define BYTE_ORDER LITTLE_ENDIAN
+#else
+#define BYTE_ORDER BIG_ENDIAN
+#endif
+
+#elif defined(__linux__)
+#include <endian.h>
+
+#elif defined(__sun) || defined(_AIX) || defined(__hpux)
+#include <sys/types.h>
+#include <arpa/nameser_compat.h>
+
+#elif defined(__sgi)
+#include <standards.h>
+#include <sys/endian.h>
+
+#else
+#include_next <machine/endian.h>
+
+#endif
+
+#endif
diff --git a/include/sys/types.h b/include/sys/types.h
index 109640b..d1c871f 100644
--- a/include/sys/types.h
+++ b/include/sys/types.h
@@ -30,4 +30,8 @@ typedef uint16_t    u_int16_t;
 typedef uint32_t    u_int32_t;
 typedef uint64_t    u_int64_t;
 
+#ifndef BYTE_ORDER
+#include <machine/endian.h>
+#endif
+
 #endif