async.gemspec in async-1.2.2 vs async.gemspec in async-1.3.0

@@ -1,6 +1,6 @@
-# -*- encoding: utf-8 -*-
+
 require_relative 'lib/async/version'
 
 Gem::Specification.new do |spec|
 	spec.name          = "async"
 	spec.version       = Async::VERSION
@@ -19,12 +19,12 @@
 	spec.executables   = spec.files.grep(%r{^bin/}).map{ |f| File.basename(f) }
 	spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
 	spec.require_paths = ["lib"]
 	spec.has_rdoc      = "yard"
 	
-	spec.required_ruby_version = "~> 2.0"
+	spec.required_ruby_version = ">= 2.2.7"
 
-	spec.add_runtime_dependency "nio4r"
+	spec.add_runtime_dependency "nio4r", "~> 2.0"
 	spec.add_runtime_dependency "timers", "~> 4.1"
 	
 	spec.add_development_dependency "async-rspec", "~> 1.1"
 	
 	spec.add_development_dependency "bundler", "~> 1.3"