If you do not have a local setup with at least php 5.6, please use the provided VM via vagrant:
vagrant up
vagrant ssh
php vendor/bin/codecept run unit
php vendor/bin/codecept run integration
php vendor/bin/codecept generate:phpunit <suite> <ClassName>
E.g: php vendor/bin/codecept generate:phpunit unit TestWorkshop/FizzBuzz/Foo
php vendor/bin/phpmetrics --report-html=fizzBuzzMetrics.html src --offline