require 'onedrb'

class Fun
  def go(s, age: '22')
    "hello %s; age: %s" % [s, age]
  end
end

fun = OneDrb::Server.new host: '127.0.0.1', port: '57844', obj: Fun.new
fun.start

require 'onedrb'

fun = OneDrb::Client.new host: '127.0.0.1', port: '57844'
fun.go 'James', age: '34'
#=> "hello James; age: 34"