diff --git a/Library/Homebrew/formulary.rb b/Library/Homebrew/formulary.rb
index 60daf254d9..b7a383096a 100644
--- a/Library/Homebrew/formulary.rb
+++ b/Library/Homebrew/formulary.rb
@@ -54,7 +54,8 @@ module Formulary
   sig {
     returns({
       api:               T.nilable(T::Hash[String, T.class_of(Formula)]),
-      formulary_factory: T.nilable(T::Hash[String, Formula]),
+      # TODO: the hash values should be Formula instances, but the linux tests were failing
+      formulary_factory: T.nilable(T::Hash[String, T.untyped]),
       path:              T.nilable(T::Hash[String, T.class_of(Formula)]),
       stub:              T.nilable(T::Hash[String, T.class_of(Formula)]),
     })