package 'test.pm' use Moose; use File::Temp; has 'tempfile' => ( is => 'rw', isa => 'File::Temp' ); sub BUILD { my $self = shift; my $args = shift; $self->{tempfile} = File::Temp->new(UNLINK => 1, SUFFIX => '.tmp'); print $self->{tempfile} "I am here"; }