* Prerequisites

  1. Make sure you have bison (http://www.gnu.org/software/bison/) installed in your system.
  2. Make sure you have ruby installed in your system (required to build).

* Compilation and Installation

  1. Run make in the top directory.

     This command will create a build directory with a directory for the host environment
     and one for each crossbuild environment based on the settings in the build_config.rb
     file.

     Assuming a default build, each of the environment directories will have the following
     important directories:

       * bin - The binary executables for this environment
       * lib - The libraries for this environment

     You can find the header files in the include directory at the root of the project.

     You can directly invoke 'minirake' with the following command:

        $ ruby ./minirake

If an error occurs when compiling mruby, it will be helpful for others if you
send a detailed report to the developers that includes the error log, machine,
and OS type.


* Adding existing gems

Gems from the [list of mruby gems](http://www.mruby.org/libraries/) can be added by adding
their respective GitHub URLs to build_config.rb. For example, to add implementations of the
File and IO Ruby core classes to mruby, insert the following in build_config.rb under the
comment section `Use mrbgems`:

    conf.gem :git => 'git@github.com:iij/mruby-io.git', :branch => 'master'

    Afterwards, re-run:

        ruby ./minirake


* Porting to other platforms


That's all.