`with_options` doesn't do deep merge

      with_options documentation: {required: true, type: 'integer'} do
        expose :posts_count, as: :posts, documentation: {example: 7}
        expose :followers_count, as: :followers, documentation: {example: 105}
        expose :following_count, as: :following, documentation: {example: 52}
        expose :bookmarks_count, as: :bookmarks, documentation: {example: 22}
      end

the example doesn't work, since documentation from nested attributes overrides parent's one.

I think they should be deep merged

Start at the with_options entry point and trace how parent and nested documentation options are combined. Reproduce the example from the issue, then add a regression test showing that nested attributes retain required and type while adding example values. Done means the nested documentation is deep-merged rather than replaced.