It's written in Guile, which is a variant of Scheme. #: is used as the keyword indicator, not an uninterned symbol like in CL. > Why does gnu-build-system use

It's written in Guile, which is a variant of Scheme. #: is used as the keyword indicator, not an uninterned symbol like in CL. > Why does gnu-build-system use %standard-phases (a symbol with %) AFAIK %symbol indicates a constant in Scheme. It's unfortunate that it isn't written in Common Lisp. CLOS would've been immensely useful there instead of the ad-hoc object system via Scheme records.