Anything that supports pipes and signals, and is easy to install. I've started using Steel Bank Common Lisp (SBCL) because it's the default implementation used with the Roswell installer.

https://github.com/roswell/roswell

(As a side-note: Perl 5 was really the ideal language for this, by design; we might be in a different world today if it hadn't been derailed by Perl Forever^W 6).