How can I remove a default gem? ! want to uninstall a gem 1.7.7 version of json

Question

I have the same rails app in OSX and Ubuntu, I want to use Zeus to speed up my rspec. In Ubuntu, Zeus starts Ok, but in OSX it always be crashed. At last I find the issue,

Answer 1

I have been experiencing a problem with default versions of gems, and the accepted answer did not work for me. What worked for me was to install the same version as the default, but without the default flag, and then uninstall it.

gem install json -v '1.7.7'

Then once that is finished:

gem uninstall json -v '1.7.7'