dryad-cluster.gemspec in dryad-0.1.1

- old
+ new

@@ -20,9 +20,10 @@
   spec.bindir        = "exe"
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
   spec.add_dependency "dryad-core", Dryad::Cluster::VERSION
+  spec.add_dependency "concurrent-ruby", "~> 1.1", ">= 1.1.5"
 
   spec.add_development_dependency "bundler", "~> 2.0"
   spec.add_development_dependency "rake", "~> 10.0"
   spec.add_development_dependency "rspec", "~> 3.0"
 end