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.