ruby/setup-ruby

Install Ruby and, with one input, install and cache your gems via Bundler.

Community actionCategory: Language & Toolchain SetupLatest v1View on GitHub

What it does

ruby/setup-ruby installs a Ruby version (faster than the runner default) and, when bundler-cache: true, runs bundle install and caches the installed gems keyed on Gemfile.lock.

It reads the version from .ruby-version or .tool-versions automatically when present.

Usage

workflow (.yml)

steps:
  - uses: actions/checkout@v4
  - uses: ruby/setup-ruby@v1
    with:
      ruby-version: '3.3'
      bundler-cache: true
  - run: bundle exec rake

Inputs

Input	Description	Default	Required
`ruby-version`	Ruby version, e.g. 3.3. Reads .ruby-version if omitted.	`.ruby-version`	No
`bundler-cache`	Run bundle install and cache the gems.	`false`	No
`working-directory`	Directory containing the Gemfile.	`.`	No

Outputs

Output	Description
`ruby-prefix`	Install path of the Ruby.
`ruby-platform`	The platform of the installed Ruby.

Notes

bundler-cache: true replaces a separate bundle install plus actions/cache step.

Common errors

A slow job re-running bundle install every time usually has bundler-cache unset. Set it to true.
A Gemfile in a subfolder needs working-directory set so caching keys on the right lockfile.

Security and pinning

Pin to a commit SHA (the @v1 tag moves).

Frequently asked questions

Do I need a separate cache step for gems?

No. Set bundler-cache: true and setup-ruby runs bundle install and caches the gems for you.

References

GitHub Actions documentation