Magento 2 Marketplace Upload Validation Tool (Quick Note)
Part of the submission process includes zipping up a composer archive and submitting it to Magento. The script Alan Kent provided performs some basic validation on that archive to make sure its something the Marketplace system will be able to work with.
It’s a little weird that this sort of validation won’t be included in Marketplace, or that the messaging around the validation isn’t clear, but the validation program is welcome regardless.