ABCL - Release notes v0.25. New version out and ABCL is increasingly developing into a really usable Common Lisp implementation. Since it runs on the JVM, you also have easy access to many libraries (if you want to) and since 0.24, Quicklisp also runs smoothly with ABCL, giving you easy access to many Common Lisp libraries. However, there are some issues with the CL libraries, as many programmers do not consider ABCL (and there are still deficiencies in the CLOS area).