diff --git a/internal/macse/secure_enclave.h b/internal/macse/secure_enclave.h
index 7fc588b..a828101 100644
--- a/internal/macse/secure_enclave.h
+++ b/internal/macse/secure_enclave.h
@@ -1,3 +1,5 @@
+//go:build darwin
+
 #ifndef SECURE_ENCLAVE_H
 #define SECURE_ENCLAVE_H
 
diff --git a/internal/macse/secure_enclave.m b/internal/macse/secure_enclave.m
index 9cbfd2a..180754c 100644
--- a/internal/macse/secure_enclave.m
+++ b/internal/macse/secure_enclave.m
@@ -1,3 +1,5 @@
+//go:build darwin
+
 #import <Foundation/Foundation.h>
 #import <Security/Security.h>
 #include "secure_enclave.h"