diff --git a/include/sxt/sxtkey.h b/include/sxt/sxtkey.h
index 29b2184..b1dc5db 100644
--- a/include/sxt/sxtkey.h
+++ b/include/sxt/sxtkey.h
@@ -110,6 +110,9 @@ int sxt_key_export_priv_file(const sxtkey_t *key, const char *file, const char *
                              int (*ask_passkey)(char *pkbuf, size_t length, int confirm, void *priv),
                              void *priv);
 
+/* export a public key to a given file */
+int sxt_key_export_public_file(const sxtkey_t *key, const char *file);
+
 /* key custom hash ops */
 /* assign a 64bit hash, 0 mean there are no hash */
 int sxt_key_assign_hash(sxtkey_t *, uint64_t);
diff --git a/sxt/ed25519.c b/sxt/ed25519.c
index 9faea8e..f1d9afd 100644
--- a/sxt/ed25519.c
+++ b/sxt/ed25519.c
@@ -7,6 +7,7 @@
 #include "config.h"
 
 #include <stdint.h>
+#include <sys/types.h>
 #include <sxt/ge25519.h>
 #include <sxt/sxtkey.h>
 #include <sxt/ciphers.h>