use Cache::File;

...

has _cache => (isa => 'Cache', is => 'rw', default => sub{ new Cache::File(cache_root => '/tmp/cacheroot')});

...

my $value = $self->_cache->get($key);
unless ($value) {
  $value = do_operation(...);
  $self->_cache->set($key,'1 hour');
}
return $value;