I would like to set up my several shared hosted websites so that each server runs as a separate user.
I would also like to use SSL, to get password encryption for stuff like mediawiki passwords.
But I would like all the servers to use the same SSL certifucarte, since I have to pay for the privilege.
Unfortunately, the shared hosting service I use only allows different domains and subdomains to run as different users. It apparently does not allow different paths within the same domain, e.g. https://glew.ca/andy, to run as different users.
So it appears that, unless I pay for more certificates, or give in and run my own server computer, rather than just using shared hosting, I can have either SSL, or separate users - but not both.
(If they allowed wildcard certificates... but they don't. Or if they allowed setuid or the equivalent... but they don't.)