diff --git a/src/buffer.hh b/src/buffer.hh
index a586e828..24509ba9 100644
--- a/src/buffer.hh
+++ b/src/buffer.hh
@@ -12,6 +12,7 @@
 #include "value.hh"
 #include "vector.hh"
 
+#include <sys/types.h>
 #include <ctime>
 
 namespace Kakoune