Lisp users generally treat libraries the same way C people do and vendor anything that's truly important. There's ocicl if you want something more scalable.

https://github.com/ocicl/ocicl

(Lisp users are generally very anachronistic people who don't understand dependency management nor know how to resolve diamond dependency issues, ocicl is one of the better approaches along with CLPM but they both get a lot of pushback from the community which "don't see a need".