Start another Ruby process and manipulate it almost seamlessly.


The CSV lib will not be loaded in the main process and the writing of the file will also take place in another process.

require "rubygems"
require "ruby_process" do |rp|
  rp.static(:Object, :require, "csv")

  rp.static(:CSV, :open, "test.csv", "w") do |csv|
    csv << ["ID", "Name"]
    csv << [1, "Kasper"]


Add to your Gemfile and bundle.

gem "ruby_process"


With a block. do |rp|
  rp.static(:File, :open, "some_file", "w") do |fp|

Almost seamless mode with ClassProxy. do |data|
  sp = data[:subproc]
  sp.static(:Object, :require, "tempfile")

  # Tempfile will be created in the subprocess and not in the current process.
  temp_file = RubyProcess::ClassProxy::Tempfile("temp")

As a variable.

rp = false)
test_string =, "Test")

Calling static methods on classes.

rp.static(:File, :open, "file_path", "w")

Spawning new objects.

file =, "file_path", "r")

Serializing objects back to the main process.

rp.static(:File, :size, "file_path") #=> RubyProcess::ProxyObject
rp.static(:File, :size, "file_path").__rp_marshall #=> 2048

Contributing to RubyProcess

  • Check out the latest master to make sure the feature hasn't been implemented or the bug hasn't been fixed yet.
  • Check out the issue tracker to make sure someone already hasn't requested it and/or contributed it.
  • Fork the project.
  • Start a feature/bugfix branch.
  • Commit and push until you are happy with your contribution.
  • Make sure to add tests for it. This is important so I don't break it in a future version unintentionally.
  • Please try not to mess with the Rakefile, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.

Copyright (c) 2012 Kasper Johansen. See LICENSE.txt for further details.