/usr/lib/ruby/ is in ruby-merb-helpers 1.1.3-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/merb-helpers/
/usr/lib/ruby/vendor_ruby/merb-helpers/tag_helpers.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/version.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/form/
/usr/lib/ruby/vendor_ruby/merb-helpers/form/helpers.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/form/builder.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/date_time_helpers.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/core_ext/
/usr/lib/ruby/vendor_ruby/merb-helpers/core_ext/numeric.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/date_time_formatting.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/text_helpers.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/time_dsl.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/core_ext.rb
/usr/lib/ruby/vendor_ruby/merb-helpers/form_helpers.rb
/usr/lib/ruby/vendor_ruby/merb-helpers.rb