Celluloid is great but not really maintained anymore.<p>You probably want to use <a href="https://github.com/ruby-concurrency/concurrent-ruby" rel="nofollow">https://github.com/ruby-concurrency/concurrent-ruby</a> and inparticular if you are interested in the Actor model take a look at <a href="http://ruby-concurrency.github.io/concurrent-ruby/Concurrent/Actor.html" rel="nofollow">http://ruby-concurrency.github.io/concurrent-ruby/Concurrent...</a> and <a href="https://github.com/ruby-concurrency/concurrent-ruby/blob/master/lib/concurrent/actor.rb" rel="nofollow">https://github.com/ruby-concurrency/concurrent-ruby/blob/mas...</a><p>I don't really write Ruby much anymore professionally but this is what I have moved a lot of my Celluloid based personal projects to.
Sidekiq moved from Celluloid to Concurrent Ruby as well.<p><a href="https://github.com/mperham/sidekiq/issues/2583" rel="nofollow">https://github.com/mperham/sidekiq/issues/2583</a>
<a href="http://www.mikeperham.com/2015/10/14/optimizing-sidekiq/" rel="nofollow">http://www.mikeperham.com/2015/10/14/optimizing-sidekiq/</a><p>Celluloid uses 1 thread per actor.