diff --git a/api/limiter.js b/api/limiter.js
index 477c715e..f6fc80cf 100644
--- a/api/limiter.js
+++ b/api/limiter.js
@@ -1,3 +1,5 @@
+"use strict"
+
 var FRAME_BUDGET = 16 // 60 frames per second = 1 call per 16 ms
 
 module.exports = function($window, render) {
diff --git a/api/router.js b/api/router.js
index eabd0e4c..4da9795d 100644
--- a/api/router.js
+++ b/api/router.js
@@ -1,3 +1,5 @@
+"use strict"
+
 var createRenderer = require("../render/render")
 var createRouter = require("../router/router")
 var limiter = require("./limiter")