diff --git a/appveyor.yml b/appveyor.yml
index 74cc6febb..a91834cef 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -39,4 +39,4 @@ install:
 build_script:
   - set YACC=.\win_flex_bison\win_bison.exe
   - set MRUBY_CONFIG=appveyor_config.rb
-  - ruby .\minirake test
+  - rake -E $stdout.sync=true test