diff --git a/extra/io/windows/files/unique/unique.factor b/extra/io/windows/files/unique/unique.factor
index ae06090488..dd0341162b 100644
--- a/extra/io/windows/files/unique/unique.factor
+++ b/extra/io/windows/files/unique/unique.factor
@@ -1,4 +1,5 @@
-USING: kernel system io.files.unique.backend ;
+USING: kernel system io.files.unique.backend
+windows.kernel32 io.windows io.nonblocking ;
 IN: io.windows.files.unique
 
 M: windows-io (make-unique-file) ( path -- stream )