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benchmark Remove benchmarks not in mruby Apr 24, 2015
bin add mruby sources Apr 20, 2012
doc fix syntax highlighting Apr 13, 2016
examples Added example for cross-compiling on Intel Edison Mar 7, 2016
include add mrb_int_mul_overflow(); close #3149 May 10, 2016
lib/mruby Change to to make Ruby 1.9 Happy Sep 7, 2015
mrbgems fixed remaining bugs in OP_ASGN stack adjustment; close #3159 May 16, 2016
mrblib suppress "can't convert Float into Integer" in Enumerable#hash Feb 16, 2016
src use mrb_int_mul_overflow() May 10, 2016
tasks Avoid Syntax Error on CRuby v1.8 Apr 16, 2016
test remove wrong ISO section from safe navigation test; ref 4c1ce0f Mar 24, 2016
.gitignore Move guides location Oct 8, 2015
.travis.yml Test against latest xcode Dec 7, 2015
.yardopts Improved mrb_args_format table Oct 20, 2015
AUTHORS mruby-1.2.0 Nov 17, 2015 Fix typos in documentation and error messages [skip ci] Jun 19, 2015
ChangeLog add document Apr 20, 2012
LEGAL Change mruby-random License to MIT Apr 8, 2013
MITL Update license year range to 2016 Jan 18, 2016
Makefile remove trailing spaces Apr 30, 2014
NEWS add document Apr 20, 2012 Small grammar fix Jan 19, 2016
Rakefile fix `rake doc` error Oct 9, 2015
TODO update TODO entries; close #2831 Nov 17, 2015
appveyor.yml Add appveyor.yml for Visual Studio 2015/2013 Mar 15, 2016
appveyor_config.rb Create appveyor_config.rb Mar 15, 2016
build_config.rb Add default benchmark build config Mar 4, 2016
minirake Correctly handle relative paths Jan 7, 2015
mruby-source.gemspec Switch gem API to constants only Sep 6, 2015
travis_config.rb Enable full-debug build on travis using `MRB_ENABLE_DEBUG_HOOK` Nov 17, 2015

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 1.2.0 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.

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