json support on ruby ?

Hello, Few days ago, the last version of Rails was out. I can see, with the following Dockerfile, that json support was dropped ************************************************************************ FROM fedora:latest RUN dnf -y update RUN dnf -y install @development-tools ruby{,-devel,gems} wget redhat-rpm-config zlib-devel libxml2-devel libxslt-devel RUN wget -O /tmp/test.rb https://gist.githubusercontent.com/anonymous/5ddaa37e8ebcae88dd5e2f056b6b... RUN gem install nokogiri -- --use-system-libraries RUN gem update --system RUN gem update RUN gem install bundler RUN ruby /tmp/test.rb ************************************************************************ Is there any steps to do to add json support or Ruby (2.3.1) on fedora (24). Regards,