diff --git a/src/index.js b/src/index.js
index e2f1f11..dcdad5b 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,5 +1,5 @@
 /* eslint-disable no-eval */
-var os = require('os');
+const os = require('os');
 
 function getPredicate (line) {
   return /\/\/ #if (.*)/.exec(line)[1]