The root package implements a convenient security backdoor for Unix with CMUCL:

  (as-superuser ...)

So that you can run lisp as a normal user, but temporarily switch to root at will.

If you are concerned about local root exploits, you probably don't want to use this package. Otherwise, it's a way to make privileged system calls without having to run as root all the time (mucking up your file permissions and so on).

A better way to do this would be to use the sudo command instead - and it provides for security too.