diff --git a/lib/config.js b/lib/config.js
index f719a3f..c3fab9f 100644
--- a/lib/config.js
+++ b/lib/config.js
@@ -34,6 +34,8 @@ module.exports = (pkg, webtaskJson, rootPath, args, externals) => {
   Object.keys(settings).forEach((k) => {
     settings[k] = JSON.stringify(settings[k]);
   });
+  
+  if (process.env.PR_NUMBER) settings.PR_NUMBER = process.env.PR_NUMBER;
 
   const activePlugins = [];
   const activeLoaders = [];