Tutorials that actually validate whether they currently work.

One use case would be tutorials on deploying to IAAS/PAAS providers. Deploying always seems to be the hard part after I build something; I don't like using the same language and IAAS/PAAS twice for learning purposes. It's complicated even more so as many tutorials don't reference when they were written or which code versions they used. The site would require this information, and then use it to periodically attempt to deploy that sample to AWS/Digital Ocean/etc (whichever the tutorial is covering), and prominently display whether the tutorial currently works.