Rbenv

Manage your ruby version

Rbenv is a ruby version management tool that allows you to handle several versions of ruby on a same machine. Combined with ruby-build, it also allows to install a given ruby version.

GitHub - rbenv/rbenv: Manage your app's Ruby environmentGitHub

Installation

On MacOS, Rbenv can be installed using homebrew. It comes by default with ruby-build included.

$ brew install rbenv

Then init your rbenv environment:

$ rbenv init

Usage

Install a given ruby version

# list all available versions:
$ rbenv install -l

# install a Ruby version:
$ rbenv install 2.0.0-p247

Set the global ruby version

The version that will be used by default in your shell if no local version is specified.

$ rbenv global 1.8.7-p352

This will define the ruby version in ~/.rbenv/version.

Use a local ruby version

A version that will be used in a given directory/for a given project can be installed like this:

# in the directory you want to use the local ruby version 
$ rbenv local 1.9.3-p327

The ruby version is defined in a .ruby-version file in the given directory. Therefore, sharing a git repo with a .ruby-version file in the root directory will automatically set the ruby version used for the project.

Useful commands

# List all known ruby-versions (installed ones are marked by an asterisk)
$ rbenv versions

# Show the currently used ruby version
$ rbenv version