The libffi library provides a portable, high level programming interface
to various calling conventions. This allows a programmer to call any
function specified by a call interface description at run-time.

FFI stands for Foreign Function Interface. A foreign function interface
is the popular name for the interface that allows code written in one
language to call code written in another language. The libffi library
really only provides the lowest, machine dependent layer of a fully
featured foreign function interface. A layer must exist above libffi
that handles type conversions for values passed between the two
languages.