diff --git a/appveyor.yml b/appveyor.yml
index f0d411c..f338747 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -22,5 +22,5 @@ install:
   - dep ensure -v
 
 build_script:
-  - go build ledger.go apduWrapper.go
+  - go build ledger.go apduWrapper.go -x
   - go test