--- src/keychain_mac.cpp
+++ src/keychain_mac.cpp	2026-05-02 05:17:32.000000000 +0800
@@ -29,6 +29,11 @@
 
 #include <AvailabilityMacros.h>
 
+/* Leopard does not have this */
+#ifndef errSecSuccess
+#define errSecSuccess 0
+#endif
+
 #include "keychain.h"
 
 namespace {