There are more than you might realize. Some good ones listed here:
https://ankane.org/new-ml-gems https://ankane.org/more-ml-gems
https://ankane.org/new-ml-gems https://ankane.org/more-ml-gems
I hadn't seen either of these, and I didn't think I was interested in ML, until I got to the Natural Language Processing section, this is a great article!
Happy Ruby Upgrade Day!