Add Generate Ruby Version And Gemset Files With RVM as a ruby til

README.md

@@ -10,7 +10,7 @@ smart people at [Hashrocket](http://hashrocket.com/).
 For a steady stream of TILs from a variety of rocketeers, checkout
 [til.hashrocket.com](https://til.hashrocket.com/).
 
-_720 TILs and counting..._
+_721 TILs and counting..._
 
 ---
 
@@ -564,6 +564,7 @@ _720 TILs and counting..._
 - [FactoryGirl Sequences](ruby/factory-girl-sequences.md)
 - [Fail](ruby/fail.md)
 - [Finding The Source of Ruby Methods](ruby/finding-the-source-of-ruby-methods.md)
+- [Generate Ruby Version And Gemset Files With RVM](ruby/generate-ruby-version-and-gemset-files-with-rvm.md)
 - [Identify Outdated Gems](ruby/identify-outdated-gems.md)
 - [If You Detect None](ruby/if-you-detect-none.md)
 - [Ins And Outs Of Pry](ruby/ins-and-outs-of-pry.md)

ruby/generate-ruby-version-and-gemset-files-with-rvm.md

@@ -0,0 +1,14 @@
+# Generate Ruby Version And Gemset Files With RVM
+
+[RVM](https://rvm.io), 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.
+
+```bash
+$ 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.