libyaml

Ubuntu 20.04. Trying to install Ruby 3.2.2 I get the following error: /tmp/ruby-build.20230911110842.25159.uzwoaP/ruby-3.2.2/lib/yaml.rb:3: warning: It seems your ruby installation is missing psych (for YAML output). To eliminate this warning, please install libyaml and reinstall your ruby. So I go on…