diff --git a/appveyor.yml b/appveyor.yml
index 1a0ed025..b03d8ad6 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,5 +1,6 @@
 version: '{build}'
 environment:
+  COVERAGE: true
   matrix:
   - arch: 32
     python: 35