Scsh

Scsh (a "Scheme shell") is computer software, a type of shell for an operating system. It is a Portable Operating System Interface (POSIX) application programming interface (API) layered on the programming language Scheme, in a manner to make the most of Scheme's ability for scripting. Scsh is limited to 32-bit platforms but there is a development version against the latest Scheme 48 that works in 64-bit mode. It is free and open-source software released under a BSD license.
Features.
Scsh includes these notable features:
Example.
 (with-cwd dir
 (filter file-executable? (directory-files dir #t))))
(for-each writeln
 (append-map executables ((infix-splitter ":") (getenv "PATH"))))
"Acknowledgments".
The reference manual for Scsh includes a spoof Acknowledgments section written by Olin Shivers. It starts:
and concludes with: