Generate Ruby Version and Gemset Files With RVM
RVM, the ruby version manager, is a fairly flexible tool
that supports a number of workflows. The rvm utility can be used to
generate both a .ruby-version file and a .ruby-gemset file for a given
project.
$ rvm --ruby-version use 2.5.3@my_project
This will generate a .ruby-version file in your current project directory
that points RVM to the 2.5.3 version of Ruby. It will also create a
.ruby-gemset file that RVM will use for managing this project's gemset.