CFFI, the Common Foreign Function Interface, purports to be a portable foreign function interface for Common Lisp. The CFFI library is composed of a Lisp-implementation-specific backend in the CFFI-SYS package, and a portable frontend in the CFFI package. The CFFI-SYS backend package defines a low-level interface to the native FFI support in the Lisp implementation. It offers operators for allocat