mruby

• What is mruby
• How to get mruby
• mruby homepage
• Mailing list
• How to compile, test, and install (mruby and gems)
• Amalgamation (single-file build)
• Building documentation
• How to customize mruby (mrbgems)
• Index of Document
• License
• Note for License
• How to Contribute
• Contributors

mruby is the lightweight implementation of the Ruby language complying to (part of) the ISO standard with more recent features provided by Ruby 4.x. Also, its syntax is Ruby 4.x compatible.

You can link and embed mruby within your application. The "mruby" interpreter program and the interactive "mirb" shell are provided as examples. You can also compile Ruby programs into compiled byte code using the "mrbc" compiler. All these tools are located in the "bin" directory. "mrbc" can also 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.

To get mruby, you can download a release from the official mruby GitHub repository or clone the trunk of the mruby source tree with the "git clone" command. You can also install and compile mruby using ruby-install, ruby-build, rvm, conda or Homebrew.

Releases, including release candidates, are published on the releases page: https://github.com/mruby/mruby/releases. Download the mruby-<version>.tar.gz, .tar.xz or .zip attached to a release. The "Source code" archives GitHub generates for a tag, and the ZIP of the master branch, leave out the Prism parser that mruby-compiler carries as a git submodule, so they do not build.

The trunk of the mruby source tree can be checked out with the following command; the --recursive fetches that submodule as well:

$ git clone --recursive https://github.com/mruby/mruby.git

In a clone made without it, rake fetches the submodule on the first build.

The URL of the mruby homepage is: https://mruby.org.

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

For the simplest case, type

rake all test

See the compile.md file for the detail.

mruby supports amalgamation, which combines all source files into a single mruby.c and mruby.h for easy embedding (similar to SQLite).

rake amalgam

Output files are generated in build/host/amalgam/. To use:

gcc -I./build/host/amalgam your_app.c ./build/host/amalgam/mruby.c -o your_app -lm

There are two sets of documentation in mruby: the mruby API (generated by YARD) and C API (Doxygen and Graphviz)

To build both of them, simply go

rake doc

You can also view them in your browser

rake view_api
rake view_capi

mruby contains a package manager called "mrbgems" that you can use to create extensions in C and/or Ruby. For a guide on how to use mrbgems, consult the mrbgems.md file, and for example code, refer to the examples/mrbgems/ folder.

• About the Limitations of mruby
• About Amalgamation (Single-File Build)
• C API Reference
• About the Compile
• About the Debugger with the mrdb Command
• About GC Arena
• Getting Started with mruby
• About the mruby directory structure
• About Linking with libmruby
• About Memory Allocator Customization and Heap Regions
• About Build-time Configurations
• About the Build-time Library Manager
• ROM Method Tables for Memory-Efficient Method Registration
• About the Symbols
• Internal Implementation / About mruby Architecture
• Internal Implementation / About Value Boxing
• Internal Implementation / About mruby Virtual Machine Instructions

mruby is released under the MIT 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.

To contribute to mruby, please refer to the contribution guidelines and send a pull request to the mruby GitHub repository. By contributing, you grant non-exclusive rights to your code under the MIT License.