Table of Contents


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TruffleRuby is the GraalVM high-performance implementation of the Ruby programming language.

Getting Started

TruffleRuby comes in two distributions:

  • Standalone: This only contains TruffleRuby in the Native configuration, making it a smaller download.
  • GraalVM: This includes support for other languages such as JavaScript, Python and R, and supports both the Native and JVM configurations. We recommend that you use a Ruby manager to use TruffleRuby inside GraalVM.

You can install either of those:

  • Via your Ruby manager/installer (RVM, rbenv, chruby, asdf, ruby-build, ruby-install). We recommend trying TruffleRuby dev builds which contain the latest fixes and improvements (replace VERSION by dev).


RVM:    $ rvm install truffleruby
rbenv:  $ rbenv install truffleruby-VERSION
asdf:   $ asdf install ruby truffleruby-VERSION
chruby: $ ruby-install truffleruby
        $ ruby-build truffleruby-VERSION ~/.rubies/truffleruby-VERSION


rbenv:  $ rbenv install truffleruby+graalvm-VERSION
asdf:   $ asdf install ruby truffleruby+graalvm-VERSION
chruby: $ ruby-install truffleruby-graalvm
        $ ruby-build truffleruby+graalvm-VERSION ~/.rubies/truffleruby+graalvm-VERSION
- uses: ruby/setup-ruby@v1
    ruby-version: truffleruby # or truffleruby-head, or truffleruby+graalvm or truffleruby+graalvm-head

You can use gem and bundle to install gems, as usual.

Please report any issues you might find on GitHub.


TruffleRuby aims to:

  • Run idiomatic Ruby code faster.
    • TruffleRuby is the fastest Ruby implementation for many CPU-intensive benchmarks.
  • Run Ruby code in parallel.
    • TruffleRuby does not have a global interpreter lock and runs Ruby code in parallel.
  • Support C extensions.
    • Many C extensions work out of the box, including database drivers.
  • Add fast and low-overhead interoperability with languages like Java, JavaScript, Python, and R.
  • Provide new tooling, such as debuggers and monitoring, that works across languages.
  • Provide all of the above while maintaining very high compatibility with the standard implementation of Ruby.

TruffleRuby Runtime Configurations

There are two main runtime configurations of TruffleRuby, Native and JVM, which have different trade-offs.

Configuration: Native (--native, default) JVM (--jvm)
Time to start TruffleRuby about as fast as MRI startup slower
Time to reach peak performance faster slower
Peak performance (also considering GC) good best
Java host interoperability needs reflection configuration just works

To find out which runtime configuration is being used, run ruby --version on the command line, or check the value of RUBY_DESCRIPTION or TruffleRuby.native? in Ruby code. Runtime configurations are further detailed in Deploying TruffleRuby.

System Compatibility

TruffleRuby is actively tested on the following systems:

  • Oracle Linux 7, 8
  • Ubuntu 16.04, 18.04, 20.04, 22.04 (all LTS)
  • Fedora 35, 36
  • macOS 10.14 (Mojave), 12 (Monterey)


  • AMD64 (aka x86_64): Supported
  • AArch64 (aka arm64): Supported on Linux (from 21.2) and on macOS (from 22.2)

You may find that TruffleRuby will not work if you severely restrict the environment, for example, by unmounting system filesystems such as /dev/shm.


  • make and gcc for building C and C++ extensions
  • libssl for the openssl C extension
  • zlib for the zlib C extension

Without these dependencies, many libraries including RubyGems will not work. TruffleRuby will try to print a nice error message if a dependency is missing, but this can only be done on a best effort basis.

You also need to set up a UTF-8 locale if not already done.

See the contributor workflow document if you wish to build TruffleRuby from source.

Current Status

We recommend that people trying TruffleRuby on their gems and applications get in touch with us for help.

TruffleRuby can run Rails and is compatible with many gems, including C extensions. However, TruffleRuby is not 100% compatible with MRI 3.0 yet. Please report any compatibility issues you might find. TruffleRuby passes around 97% of ruby/spec, more than any other alternative Ruby implementation.

TruffleRuby might not be fast yet on Rails applications and large programs. Notably, large programs currently take a long time to warmup on TruffleRuby and this is something the TruffleRuby team is currently working on. Large programs often involve more performance-critical code so there is a higher chance of hitting an area of TruffleRuby which has not been optimized yet.


TruffleRuby has the same version, and is released at the same time as GraalVM. There is a release every 3 months. See the release roadmap.

Migration from MRI

TruffleRuby should in most cases work as a drop-in replacement for MRI, but you should read about our compatibility.

Migration from JRuby

For many use cases TruffleRuby should work as a drop-in replacement for JRuby. However, our approach to integration with Java is different to JRuby so you should read our migration guide.


The best way to get in touch with us is to join the #truffleruby channel on GraalVM Slack. You can also Tweet to @TruffleRuby, or email

Please report security vulnerabilities via the process outlined in the reporting vulnerabilities guide, rather than by something public such as a GitHub issue or a Gitter conversation.

Mailing List

Announcements about GraalVM, including TruffleRuby, are made on the graal-dev mailing list.


The main authors of TruffleRuby ordered by first contribution are: Chris Seaton, Benoit Daloze, Kevin Menard, Petr Chalupa, Brandon Fish, Duncan MacGregor, Christian Wirth, Rafael França, Alan Wu, Nicolas Laurent, Carol Chen, Nikolay Sverchkov, Lillian Zhang, Tom Stuart, and Maple Ong.


See SECURITY for how to report security vulnerabilities to Oracle. For known vulnerabilities in Ruby, please refer to the known-cves file.


TruffleRuby is copyright (c) 2013-2022 Oracle and/or its affiliates, and is made available to you under the terms of any one of the following three licenses:

  • Eclipse Public License version 2.0, or
  • GNU General Public License version 2, or
  • GNU Lesser General Public License version 2.1.

For further licensing information, see LICENCE, 3rd_party_licenses, and doc/legal/legal.


TruffleRuby includes infrastructure code from JRuby (e.g. parser, JCodings, Joni), core library code from the Rubinius project, as well as code from the standard implementation of Ruby, MRI.