clesh
Clesh is a very short program that provides mechanisms for running and composing Unix shell commands and constructs from Common Lisp. Essentially, it provides a '!' syntax that you can use to run commands and a '[]' embedded mode where you can enter bash scripts and obtain the standard output as a lisp string, and some other features. Lisp expressions can be included in any command or script using a '?' syntax. Clesh works on every implementation of Common Lisp that is supported by trivial-shell.
$ area51 add cleshCopyUsage
;; area51 add updates your .asd automatically.
;; Use the package in your code:
(in-package :my-project)
(clesh:some-function ...)