diff --git a/@vates/predicates/index.js b/@vates/predicates/index.js
index 023db0232..d6132eb3d 100644
--- a/@vates/predicates/index.js
+++ b/@vates/predicates/index.js
@@ -1,3 +1,5 @@
+'use strict'
+
 const {
   isArray,
   prototype: { filter },