diff --git a/build-constraints.yaml b/build-constraints.yaml
index 18ef332f..0131fdbb 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -2010,6 +2010,9 @@ package-flags:
     darcs:
         use-time-1point5: true
 
+    fay:
+        test: true
+
 # end of package-flags