rbenv is a tool for simple Ruby version management.

To install rbenv, please refer to the Readme.

See Why rbenv?

The string read from a .ruby-version file must match the name of an existing directory in ~/.rbenv/versions/. You can see the list of installed Ruby versions with rbenv versions.

If you're using ruby-build, typically this will be one of its Ruby version names.

Other version managers might allow fuzzy version matching on the string read from .ruby-version file, e.g. they might allow "1.9.3" (without patch suffix) to match the latest Ruby 1.9.3 release. rbenv will not support this, because such behavior is unpredictable and therefore harmful.

1. Check that rbenv is in your PATH:

   which rbenv

2. Check that rbenv's shims directory is in PATH:

   echo $PATH | grep --color=auto "$(rbenv root)/shims"

   If not, see the rbenv init step in installation instructions.

Typically it's one of the following:

• bash: ~/.bash_profile
• Zsh: ~/.zshrc
• other: ~/.profile

With bash on Ubuntu, you probably already have a ~/.profile. In that case you should add rbenv config there instead of creating a ~/.bash_profile. However, since this file is read only once per desktop login, you may achieve quicker results by adding rbenv to ~/.bashrc instead.

See Unix shell initialization for more info about how config files get loaded.

Rubinius in 1.9 mode uses a separate bin directory for executable binstubs. To compensate for that, use the rbx 2.0 dev fix plugin.