libmoosex-singleton-perl 0.30-1 (amd64 binary) in ubuntu cosmic

 MooseX::Singleton lets you easily change your Moose class into a singleton,
 which is a class that only has one instance in an application. All you should
 need to do is change your use of "use Moose" to "use MooseX::Singleton". This
 module uses a new class metaclass and instance metaclass, so if you're doing
 metamagic you may not be able to use this.