diff --git a/core/core_unix.go b/core/core_unix.go
index 4eb09092..af96eb7c 100644
--- a/core/core_unix.go
+++ b/core/core_unix.go
@@ -1,3 +1,5 @@
+// +build !windows
+
 package core
 
 func Shell(cmd string) (string, error) {