rvm

RVM, short for Ruby Version Manager, is a command-line tool designed to manage multiple Ruby environments on a single system. It enables installing, configuring, and switching between Ruby interpreters and associated gemsets without altering system-wide settings.

Developed by Wayne E. Seguin, RVM emerged in the late 2000s to simplify Ruby development across projects. It is an open-source project distributed from the official site and community repositories, and it remains widely used in Ruby development workflows.

Key features of RVM include the ability to install and switch between multiple Ruby versions, create separate gemsets for different projects to isolate dependencies, and manage various Ruby implementations such as MRI, JRuby, and others. RVM can install rubies from source or from pre-built binaries, typically per-user, avoiding the need for root permissions. It integrates with shells to automatically select the correct Ruby version and gemset when entering a project directory.

Installation and usage are straightforward. On macOS, RVM can be installed via a package manager or the official installer; on Linux, users can run the official installation script or use distribution package managers. Typical commands include rvm install <version>, rvm use <version>, and rvm gemset create <name> followed by rvm gemset use <name>. A common pattern is to set a default with rvm --default use <version>.

Alternatives to RVM include rbenv and asdf, which offer lighter-weight approaches to Ruby version management. RVM remains popular for its extensive feature set and built-in gemset support, though some workflows prefer simpler tools. See also Ruby, RubyGems, rbenv, asdf, and gemsets.