diff --git a/.travis.yml b/.travis.yml
index 4145d58..28f61ec 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,6 +3,10 @@ language: php
 php:
   - '7.0'
 
+env:
+  global:
+    - BUILD_LEADER_ID=1
+
 cache:
   directories:
     - $HOME/.npm