/usr/lib/ruby/ is in ruby-mixlib-install 1.1.0-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/mixlib/
/usr/lib/ruby/vendor_ruby/mixlib/install/
/usr/lib/ruby/vendor_ruby/mixlib/install/artifact_info.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/backend/
/usr/lib/ruby/vendor_ruby/mixlib/install/backend/artifactory.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/backend/base.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/backend/bintray.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/backend/omnitruck.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/backend.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/base.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne/
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne/scripts/
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne/scripts/artifactory_urls.sh.erb
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne/scripts/fetch_metadata.sh.erb
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne/scripts/fetch_package.sh
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne/scripts/helpers.sh
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne/scripts/install_package.sh
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne/scripts/platform_detection.sh
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne/scripts/script_cli_parameters.sh
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/bourne.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/powershell/
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/powershell/scripts/
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/powershell/scripts/get_project_metadata.ps1.erb
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/powershell/scripts/get_project_metadata_for_artifactory.ps1.erb
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/powershell/scripts/helpers.ps1
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/powershell/scripts/install_project.ps1
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/powershell/scripts/platform_detection.ps1
/usr/lib/ruby/vendor_ruby/mixlib/install/generator/powershell.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/generator.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/options.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/product.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/script_generator.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/util.rb
/usr/lib/ruby/vendor_ruby/mixlib/install/version.rb
/usr/lib/ruby/vendor_ruby/mixlib/install.rb