Lisp as a shell
See CLISP-Shell locally or the "official, expanded and corrected version" at the CLISP home

For portable shell scripting with CL, you may consider using inferior-shell.

Non-Common-Lisp Lisp solutions also include LUSH (the Lisp Universal Shell) or SCSH (Scheme Shell), or using the emacs' eshell…

Unix system programming