diff --git a/.circleci/config.yml b/.circleci/config.yml
index 896df666d5b..c604d0a769a 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -192,6 +192,10 @@ commands:
 
             # Install the right version of ruby
             if [[ -z "$(rbenv versions | grep << parameters.ruby_version >>)" ]]; then
+              # ensure that `ruby-build` can see all the available versions of Ruby
+              # some PRs received machines in a weird state, this should make the pipelines
+              # more robust.
+              brew update && brew upgrade ruby-build
               rbenv install << parameters.ruby_version >>
             fi