Skip to content
Lightweight Ruby
Branch: master
Clone or download
Latest commit 3e5dd40 Mar 24, 2019
Type Name Latest commit message Commit time
Failed to load latest commit information.
benchmark [ci skip] Remove no meaning statement in `bm_app_lc_fizzbuzz.rb` Jan 23, 2019
include Fix constant name validation Mar 14, 2019
tasks Refer also CXX and CC env vars as linker command in gcc and clang too… Mar 6, 2019
.gitignore [ci skip] Sort `.gitignore` Jan 15, 2019
.gitlab-ci.yml Gitlab tests for multiple configurations Feb 16, 2017
.yardopts Rename `MITL` to `LICENSE` in `.yardopts`; ref 67728c1 [ci skip] Mar 12, 2019
AUTHORS Fix typo in `AUTHORS` [ci skip] Mar 12, 2019
LICENSE Rename `MITL` to `LICENSE` to conform GitHub convention. Mar 11, 2019
Makefile remove trailing spaces Apr 30, 2014
NEWS add document Apr 20, 2012 Rename `MITL` to `LICENSE` to conform GitHub convention. Mar 11, 2019
TODO Remove things we've done in `TODO` file. Dec 20, 2018
appveyor.yml Use Rake instead of MiniRake on AppVeyor Mar 18, 2019
minirake Fix `$rake_root_fiber` checking. Dec 25, 2018
mruby-source.gemspec Switch gem API to constants only Sep 6, 2015
travis_config.rb Add `-fpermissive` to C++ compiler flags. Nov 19, 2018

Build Status

What is mruby

mruby is the lightweight implementation of the Ruby language complying to (part of) the ISO standard. Its syntax is Ruby 1.9 compatible.

mruby can be linked and embedded within your application. We provide the interpreter program "mruby" and the interactive mruby shell "mirb" as examples. You can also compile Ruby programs into compiled byte code using the mruby compiler "mrbc". All those tools reside in the "bin" directory. "mrbc" is also able to generate compiled byte code in a C source file, see the "mrbtest" program under the "test" directory for an example.

This achievement was sponsored by the Regional Innovation Creation R&D Programs of the Ministry of Economy, Trade and Industry of Japan.

How to get mruby

The stable version 2.0.0 of mruby can be downloaded via the following URL:

The latest development version of mruby can be downloaded via the following URL:

The trunk of the mruby source tree can be checked out with the following command:

$ git clone

You can also install and compile mruby using ruby-install, ruby-build or rvm.

mruby home-page

The URL of the mruby home-page is:

Mailing list

We don't have a mailing list, but you can use GitHub issues.

How to compile and install (mruby and gems)

See the doc/guides/ file.

Running Tests

To run the tests, execute the following from the project's root directory.

$ make test


$ ruby ./minirake test

How to customize mruby (mrbgems)

mruby contains a package manager called mrbgems. To create extensions in C and/or Ruby you should create a GEM. For a documentation of how to use mrbgems consult the file doc/guides/ For example code of how to use mrbgems look into the folder examples/mrbgems/.


mruby is released under the MIT License.

Note for License

mruby has chosen a MIT License due to its permissive license allowing developers to target various environments such as embedded systems. However, the license requires the display of the copyright notice and license information in manuals for instance. Doing so for big projects can be complicated or troublesome. This is why mruby has decided to display "mruby developers" as the copyright name to make it simple conventionally. In the future, mruby might ask you to distribute your new code (that you will commit,) under the MIT License as a member of "mruby developers" but contributors will keep their copyright. (We did not intend for contributors to transfer or waive their copyrights, Actual copyright holder name (contributors) will be listed in the AUTHORS file.)

Please ask us if you want to distribute your code under another license.

How to Contribute

See the contribution guidelines, and then send a pull request to We consider you have granted non-exclusive right to your contributed code under MIT license. If you want to be named as one of mruby developers, please include an update to the AUTHORS file in your pull request.

You can’t perform that action at this time.