Gemfile in postgres_ext-0.3.1 vs Gemfile in postgres_ext-0.4.0

@@ -3,10 +3,10 @@
 # Specify your gem's dependencies in postgres_ext.gemspec
 gemspec
 unless ENV['CI']
   if RUBY_PLATFORM =~ /java/
     gem 'ruby-debug'
-  elsif RUBY_VERSION == '1.9.3' || RUBY_VERSION == '2.0.0'
-    gem 'debugger'
+  elsif RUBY_VERSION == '2.0.0'
+    gem 'byebug'
   end
 end
 gem 'fivemat'