Change expansion tags
diff --git a/.appveyor.yml b/.appveyor.yml
index 6b6383c..63e7a65 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -16,7 +16,7 @@
     - OPTIONS: -Dalign_reads=ON
 
 before_build:
-  - cmd: cmake -G "Visual Studio 16 2019" -Dfatal_warnings=OFF $(OPTIONS)
+  - cmake -G "Visual Studio 16 2019" -Dfatal_warnings=OFF %OPTIONS%
 
 build:
   project: $(APPVEYOR_BUILD_FOLDER)\$(APPVEYOR_PROJECT_NAME).sln