diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 610c025..6e8a845 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -21,13 +21,13 @@ advised that you use [RVM](https://rvm.io/rvm/install).
 Once you've got that installed and configured, get the latest version of Ruby with:
 
 ```bash
-$ rvm install 2.4.2
+$ rvm install 2.4.7
 ```
 
 Select that version and then create an isolated [gemset](https://rvm.io/gemsets/basics) with:
 
 ```bash
-$ rvm use 2.4.2
+$ rvm use 2.4.7
 $ rvm gemset create autonomic
 $ rvm gemset use autonomic
 ```
@@ -58,7 +58,7 @@ You can edit content in the `.md` files under `src` and `src/_posts`.
 When you're hacking later on (or in a new shell), you'll need to run:
 
 ``` bash
-$ rvm use 2.4.2
+$ rvm use 2.4.8
 $ rvm gemset use autonomic
 ```