Download mruby

wget "https://github.com/mruby/mruby/archive/2.0.1.zip" -O ~/packages/mruby-2.0.1.zip

unzip ~/packages/mruby-2.0.1.zip -d ~/packages/

Configure mruby

Add to build_config.rb line conf.gem github: 'iij/mruby-env' for available ENV object. ... and other what you need

Build mruby

Run in source folder

./minirake

Clone example repo

git clone git@github.com:iamsimakov/mruby-usage.git && cd mruby-usage

Build example script

Run this command to export variable in current terminal session or add this line to your ~/.bashrc or another shell rc file to use this var in the future(change to your extract mruby folder)

export MRUBY_HOME=~/packages/mruby-2.0.1

And start build your script

$MRUBY_HOME/bin/mrbc -Bruby_start ruby_start.rb && gcc main.c $MRUBY_HOME/build/host/lib/libmruby.a -I $MRUBY_HOME/include/ -o run -lm

Run script:

./run