Some community members suggest that folders like
dev don't belong on a production environment. Is there an official list somewhere? What else has no place on the production server?
Is there an official list somewhere
In general the folders we exclude from production are:
/dev /downloader .htaccess.sample index.php.sample install.php LICENSE.html LICENSE.txt LICENSE_AFL.txt LICENSE_EE.html LICENSE_EE.txt mage php.ini.sample RELEASE_NOTES.txt
There are exceptions here - for instance - if you don't include the LICENSE files you may not be able to install from scratch; so you'd definitely want to have it tracked in source control, but not deployed.
Obviously it will be hard to run the installer if
install.php isn't in your source control either.
/downloader are the ones that I would advocate should never be in a production environment.