https://metacpan.org/release/SYOHEX/Mouse-v2.4.4 Mouse with threads did not work on Perl 5.22.0 or higher version. This makes Text::Xslate test failure for a long time. This version fixed the issue and works with threads. Please upgrade for newer perl users. Example We expects $foo->syntax is "Kolon" but $foo->syntax is undef with older Mouse on Perl 5.22.0 or higher. This test is passed with Mous