diff --git a/lib/github.js b/lib/github.js
index 3492a56..234bcf6 100644
--- a/lib/github.js
+++ b/lib/github.js
@@ -52,6 +52,12 @@ const splittedURL = fullURL => {
     ref = ref.substring(0, 7)
   }
 
+  // We're deploying master by default,
+  // so there's no need to indicate it explicitly
+  if (ref === 'master') {
+    ref = ''
+  }
+
   return {main, ref}
 }