diff --git a/config/boot.rb b/config/boot.rb
index 282011619..023130575 100644
--- a/config/boot.rb
+++ b/config/boot.rb
@@ -1,3 +1,5 @@
+$stdout.sync = true
+
 ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
 
 require "bundler/setup" # Set up gems listed in the Gemfile.