sub _dzil_shim {
    # shim for working on Dist::Zilla modules
 
    my ($self, $cmd_file) = @_;
 
    # return early if possible
 
    return if -e 'Build.PL' || -e 'Makefile.PL';
    return if ! -e 'dist.ini';
 
    my $log = $log->child('_dzil_shim');
    $log->_5("dzil dist... loading the shim");
 
    my $path_sep = $self->is_win ? ';' : ':';
 
    if (! grep {-x "$_/dzil"} split /$path_sep/, $ENV{PATH} ){
        $log->fatal(
            "this appears to be a Dist::Zilla module, but the dzil binary " .
            "can't be found\n"
        );
    }
 
    $self->{is_dzil} = 1;
 
    open my $fh, '<', 'dist.ini' or croak $!;
 
    my ($dist, $version);
 
    while (<$fh>){
        if (/${ re_brewbuild('extract_dzil_dist_name') }/){
            $dist = $1;
        }
        if (/${ re_brewbuild('extract_dzil_dist_version') }/){
            $version = $1;
        }
        last if $dist && $version;
    }
 
    $log->_7("running dzil commands: 'dzil authordeps --missing | cpanm', " .
             "'dzil build'"
     );
 
    `dzil authordeps --missing | cpanm`;
    `dzil clean`;
    `dzil build`;
 
    my $dir = "$dist-$version";
    copy $cmd_file, $dir if defined $cmd_file;
    chdir $dir;
    $log->_7("entered $dir directory");
}
sub _dzil_unshim {
    # unshim after doing dzil work
 
    my $self = shift;
 
    my $log = $log->child('_dzil_unshim');
 
    if (! $self->{is_dzil}){
        $log->_7("not a dzil distribution; nothing to do");
        return;
    }
 
    $log->_5("removing dzil shim");
 
    $self->{is_dzil} = 0;
    chdir '..';
    $log->_7("changed to '..' dir");
}