unable to install plugin: json dependency conflict

[lelutin]

Hello, I just tried to install the plugin with vagrant plugin install sahara and vagrant gave this error:

$ vagrant plugin install sahara
Installing the 'sahara' plugin. This can take a few minutes...
Bundler, the underlying system Vagrant uses to install plugins,
reported an error. The error is shown below. These errors are usually
caused by misconfigured plugin installations or transient network
issues. The error from Bundler is:

conflicting dependencies json (= 1.8.3) and json (= 2.1.0)
  Activated json-2.1.0
  which does not match conflicting dependency (= 1.8.3)

  Conflicting dependency chains:
    json (= 2.1.0), 2.1.0 activated

  versus:
    json (= 1.8.3)

  Gems matching json (= 1.8.3):
    json-1.8.3

I'm running debian sid with vagrant 2.0.0 and vagrant-libvirt 0.0.40