diff --git a/stack.yaml b/stack.yaml
index 7e53746..5b7712a 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -57,6 +57,8 @@ extra-deps:
 flags:
   mintty:
     Win32-2-13-1: false
+  xeno:
+    whitespace-around-equals: true
 
 # Extra package databases containing global packages
 # extra-package-dbs: []