diff --git a/src/vmspawn/vmspawn-util.c b/src/vmspawn/vmspawn-util.c
index 852a81d071..95c05643d8 100644
--- a/src/vmspawn/vmspawn-util.c
+++ b/src/vmspawn/vmspawn-util.c
@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
 #include <stdio.h>
+#include <unistd.h>
 
 #include "alloc-util.h"
 #include "architecture.h"