MRuby::Build.new do |conf|

    # ... (snip) ...

    conf.gem :github => 'bamchoh/mruby-mouse-emulator'
    conf.gem :github => 'bamchoh/mruby-sleep', :branch => 'support-float-value'
end

offset = 500
radius = 250
360.times do |i|
  x = radius * Math.cos(i / 180 * Math::PI) + offset
  y = radius * Math.sin(i / 180 * Math::PI) + offset

  Mouse.move_to(x,y)
  sleep(0.01)
end