In a post to his blog Ivan Enderlin talks about a move that his team at Automattic (the company behind WordPress) made away from using PHPUnit for their application testing over to atoum and some of the reasoning behind it.

Few months ago at tagged: wordpress testing unittest atoum phpunit comparison migration

Link: https://mnt.io/2018/02/26/how-automattic-partly-moved-away-from-phpunit-to-atoum/