diff --git a/appveyor.yml b/appveyor.yml
index 542ef2a..5470392 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -10,6 +10,7 @@ environment:
   PYTHON: C:\Python27-x64
   PYTHON_VERSION: 2.7.x
   PYTHON_ARCH: 64
+  GFMXR_DEBUG: 1
 
 install:
   - set PATH=%GOPATH%\bin;C:\go\bin;%PATH%