mutex_m.gemspec in mutex_m-0.1.2 vs mutex_m.gemspec in mutex_m-0.2.0

- old
+ new

@@ -18,9 +18,10 @@
 
   spec.files         = ["Gemfile", "LICENSE.txt", "README.md", "Rakefile", "lib/mutex_m.rb", "mutex_m.gemspec"]
   spec.bindir        = "exe"
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
+  spec.required_ruby_version = '>= 2.5'
 
   spec.add_development_dependency "bundler"
   spec.add_development_dependency "rake"
   spec.add_development_dependency "test-unit"
 end