diff --git a/README.md b/README.md
index 4821599..6c9bbb0 100644
--- a/README.md
+++ b/README.md
@@ -33,7 +33,7 @@ The example enables the mprotect feature for the emacs binary:
 # As a root account
 require 'hbsdctl'
 BSD::Control
-  .feature!("mprotect")
+  .feature!(:mprotect)
   .enable!("/usr/local/bin/emacs")
 ```
 
diff --git a/lib/bsd/control.rb b/lib/bsd/control.rb
index 1566d83..81ea9f0 100644
--- a/lib/bsd/control.rb
+++ b/lib/bsd/control.rb
@@ -23,7 +23,7 @@ module BSD::Control
   # @return [BSD::Control::Feature]
   #  Returns an instance of BSD::Control::Feature.
   def self.feature!(name)
-    feature = Feature.available.find { _1.name == name }
+    feature = Feature.available.find { _1.name == name.to_s }
     feature ? feature : raise(Error, "feature '#{name}' wasn't found")
   end