Compile and install Ruby
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Add definition for JRuby and


ruby-build is an rbenv plugin that provides an rbenv install command to compile and install different versions of Ruby on UNIX-like systems.

You can also use ruby-build without rbenv in environments where you need precise control over Ruby version installation.

See the list of releases for changes in each version.


Installing as an rbenv plugin (recommended)

Installing ruby-build as an rbenv plugin will give you access to the rbenv install command.

git clone ~/.rbenv/plugins/ruby-build

This will install the latest development version of ruby-build into the ~/.rbenv/plugins/ruby-build directory. From that directory, you can check out a specific release tag. To update ruby-build, run git pull to download the latest changes.

Installing as a standalone program (advanced)

Installing ruby-build as a standalone program will give you access to the ruby-build command for precise control over Ruby version installation. If you have rbenv installed, you will also be able to use the rbenv install command.

git clone
cd ruby-build

This will install ruby-build into /usr/local. If you do not have write permission to /usr/local, you will need to run sudo ./ instead. You can install to a different prefix by setting the PREFIX environment variable.

To update ruby-build after it has been installed, run git pull in your cloned copy of the repository, then re-run the install script.

Installing with Homebrew (for OS X users)

Mac OS X users can install ruby-build with the Homebrew package manager. This will give you access to the ruby-build command. If you have rbenv installed, you will also be able to use the rbenv install command.

This is the recommended method of installation if you installed rbenv with Homebrew.

brew install ruby-build

Or, if you would like to install the latest development release:

brew install --HEAD ruby-build

To upgrade the HEAD package use --fetch-HEAD option:

brew upgrade --fetch-HEAD ruby-build


Before you begin, you should ensure that your build environment has the proper system dependencies for compiling the wanted Ruby version (see our recommendations).

Using rbenv install with rbenv

To install a Ruby version for use with rbenv, run rbenv install with the exact name of the version you want to install. For example,

rbenv install 2.2.0

Ruby versions will be installed into a directory of the same name under ~/.rbenv/versions.

To see a list of all available Ruby versions, run rbenv install --list. You may also tab-complete available Ruby versions if your rbenv installation is properly configured.

Using ruby-build standalone

If you have installed ruby-build as a standalone program, you can use the ruby-build command to compile and install Ruby versions into specific locations.

Run the ruby-build command with the exact name of the version you want to install and the full path where you want to install it. For example,

ruby-build 2.2.0 ~/local/ruby-2.2.0

To see a list of all available Ruby versions, run ruby-build --definitions.

Pass the -v or --verbose flag to ruby-build as the first argument to see what's happening under the hood.

Custom definitions

Both rbenv install and ruby-build accept a path to a custom definition file in place of a version name. Custom definitions let you develop and install versions of Ruby that are not yet supported by ruby-build.

See the ruby-build built-in definitions as a starting point for custom definition files.

Special environment variables

You can set certain environment variables to control the build process.

  • TMPDIR sets the location where ruby-build stores temporary files.
  • RUBY_BUILD_BUILD_PATH sets the location in which sources are downloaded and built. By default, this is a subdirectory of TMPDIR.
  • RUBY_BUILD_CACHE_PATH, if set, specifies a directory to use for caching downloaded package files.
  • RUBY_BUILD_MIRROR_URL overrides the default mirror URL root to one of your choosing.
  • RUBY_BUILD_SKIP_MIRROR, if set, forces ruby-build to download packages from their original source URLs instead of using a mirror.
  • RUBY_BUILD_ROOT overrides the default location from where build definitions in share/ruby-build/ are looked up.
  • RUBY_BUILD_DEFINITIONS can be a list of colon-separated paths that get additionally searched when looking up build definitions.
  • CC sets the path to the C compiler.
  • RUBY_CFLAGS lets you pass additional options to the default CFLAGS. Use this to override, for instance, the -O3 option.
  • CONFIGURE_OPTS lets you pass additional options to ./configure.
  • MAKE lets you override the command to use for make. Useful for specifying GNU make (gmake) on some systems.
  • MAKE_OPTS (or MAKEOPTS) lets you pass additional options to make.
  • MAKE_INSTALL_OPTS lets you pass additional options to make install.
  • RUBY_CONFIGURE_OPTS, RUBY_MAKE_OPTS and RUBY_MAKE_INSTALL_OPTS allow you to specify configure and make options for buildling MRI. These variables will be passed to Ruby only, not any dependent packages (e.g. libyaml).

Applying patches to Ruby before compiling

Both rbenv install and ruby-build support the --patch (-p) flag that signals that a patch from stdin should be applied to Ruby, JRuby, or Rubinius source code before the ./configure and compilation steps.

Example usage:

# applying a single patch
$ rbenv install --patch 1.9.3-p429 < /path/to/ruby.patch

# applying a patch from HTTP
$ rbenv install --patch 1.9.3-p429 < <(curl -sSL

# applying multiple patches
$ cat fix1.patch fix2.patch | rbenv install --patch 1.9.3-p429

Checksum verification

If you have the shasum, openssl, or sha256sum tool installed, ruby-build will automatically verify the SHA2 checksum of each downloaded package before installing it.

Checksums are optional and specified as anchors on the package URL in each definition. (All bundled definitions include checksums.)

Package download mirrors

ruby-build will first attempt to download package files from a mirror hosted on Amazon CloudFront. If a package is not available on the mirror, if the mirror is down, or if the download is corrupt, ruby-build will fall back to the official URL specified in the definition file.

You can point ruby-build to another mirror by specifying the RUBY_BUILD_MIRROR_URL environment variable--useful if you'd like to run your own local mirror, for example. Package mirror URLs are constructed by joining this variable with the SHA2 checksum of the package file.

If you don't have an SHA2 program installed, ruby-build will skip the download mirror and use official URLs instead. You can force ruby-build to bypass the mirror by setting the RUBY_BUILD_SKIP_MIRROR environment variable.

The official ruby-build download mirror is sponsored by Basecamp.

Package download caching

You can instruct ruby-build to keep a local cache of downloaded package files by setting the RUBY_BUILD_CACHE_PATH environment variable. When set, package files will be kept in this directory after the first successful download and reused by subsequent invocations of ruby-build and rbenv install.

The rbenv install command defaults this path to ~/.rbenv/cache, so in most cases you can enable download caching simply by creating that directory.

Keeping the build directory after installation

Both ruby-build and rbenv install accept the -k or --keep flag, which tells ruby-build to keep the downloaded source after installation. This can be useful if you need to use gdb and memprof with Ruby.

Source code will be kept in a parallel directory tree ~/.rbenv/sources when using --keep with the rbenv install command. You should specify the location of the source code with the RUBY_BUILD_BUILD_PATH environment variable when using --keep with ruby-build.

Getting Help

Please see the ruby-build wiki for solutions to common problems.

If you can't find an answer on the wiki, open an issue on the issue tracker. Be sure to include the full build log for build failures.