the scope of '$text_format' is not available to the worksheet->write line. This worked for me: 
    use strict;
    use Excel::Writer::XLSX;

    my $workbook   = Excel::Writer::XLSX->new( 'mytest.xlsx' );
    my $worksheet = $workbook->add_worksheet( 'testsheet' );

    my $text_format = $workbook->add_format(
        bold   => 1,
        italic => 1,
        color  => 'red',
        size   => 18,
        font   => 'Lucida Calligraphy'
    );


    $worksheet->write( 'A2', "Text" );
    $worksheet->write( 'B3', "Hello Excel", $text_format );
    $worksheet->write( 'B8', "Hello Excel");


    $workbook->close;

    __END__

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In reply to Re: Excel::Writer::XLSX 0 byte outfile by fionbarr
in thread Excel::Writer::XLSX 0 byte outfile by doc1623

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