How to register new version IRuby kernel?

[stardiviner]

I updated Ruby version, and manage ruby envrionment with rbenv.
Current iruby gem is installed under Ruby version 2.3.0-dev.
But jupyter kernels list does not update. I tried command iruby register --force. It does not register a new version ruby kernel. (I check out new kernel in jupyter notebook button New.)
Then I try to find out why. I checked out ~/.ipython/kernels/ruby/kernel.json. It is version 2.3.0.

{"argv":["/home/stardiviner/.gem/ruby/2.3.0/bin/iruby","kernel","{connection_file}"],
"display_name":"Ruby 2.3.0","language":"ruby"}

There is no other kenel configs under ~/.ipython/kernels/.
I don't know why jupyter notebook can't find new version ruby kernel.

[domitry]

Actually the current version of Jupyter does not seem to check files in ~/.ipython/kernels.
Instead it uses directories listed in the result of jupyter --paths.
See #56 for details.

[stardiviner]

problem solved. with command jupyter kernelspec install --user ruby.

[rattrayalex]

The above did not work for me; I had to rm -rf ~/.ipython

[jdetle]

Hey! Just found this, @stardiviner's solution worked when I changed it to jupyter kernelspec install --user ~/.ipython/kernels/ruby

[sashaegorov]

I've just installed iruby, comment above is still helpful.

[dmmfll]

I am using rvm on Ubuntu.
I have been using Jupyter with Ruby 2.3.0 for a while without issues.
I changed to Ruby 2.4. I followed all the instructions for installing iruby, yet the kernel would die every time.
I had to gem install rbczmq in addition to editing kernel.json.
Then the notebook functioned as expected with Ruby 2.4.