when I tried run this root@0b2616b0e5a8:/# gem install json getting error as Error installing json: json requires Ruby version ~> 2.0.
Try running ‘sudo apt-get install ruby2.0-dev’ first, then ‘gem2.0 install json’. That did the trick for me. See http://stackoverflow.com/questions/13767725/unable-to-install-gem-failed-to-build-gem-native-extension-cannot-load-such for more info.
Fixed with this PR.
apt-get install ruby2.0-dev didn’t work for me, had to use
to be able to run gem2.0 you need to install ruby2.0, si the command in the example should look like:
apt-get install -y ruby2.0-dev ruby2.0