diff --git a/lib/rbs_rails/active_record.rb b/lib/rbs_rails/active_record.rb
index a1e8509..70d55e6 100644
--- a/lib/rbs_rails/active_record.rb
+++ b/lib/rbs_rails/active_record.rb
@@ -496,6 +496,8 @@ def authenticate_#{attribute}: (String) -> (#{klass_name} | false)
         mod_sig = +"module GeneratedAttributeMethods\n"
         mod_sig << klass.columns.map do |col|
           col_serializer = klass.attribute_types[col.name].try(:coder)
+          puts 'Checking... ' + col.name.to_s
+          puts ' → found ' + col_serializer.inspect
           # e.g. ActiveRecord::Coders::JSON
           #      if your model has `serialize ..., JSON`
           # e.g. #<ActiveRecord::Coders::YAMLColumn:0x0000aaaafdc54970 @attr_name=..., @object_class=Array>
@@ -515,6 +517,7 @@ def authenticate_#{attribute}: (String) -> (#{klass_name} | false)
                            sql_type_to_class(col.type)
                          end
           end
+          puts '[chose ' + class_name + ']'
           class_name_opt = optional(class_name)
           # If the DB says the column can be null, we need `<type>?`
           # ...but if the type is already `untyped` there's no point in writing `untyped?`