diff --git a/src/Db.c b/src/Db.c
index 4bdfe10..22c57c1 100644
--- a/src/Db.c
+++ b/src/Db.c
@@ -29,6 +29,7 @@
 
 #include <pthread.h>
 #include <fcntl.h>
+#include <unistd.h>
 
 struct Db
 {