The two most appealing features of the LuaJIT FFI: 1) The syntax. To specify the types of the FFI functions you you use a DSL that is similar to C declarations

The two most appealing features of the LuaJIT FFI: 1) The syntax. To specify the types of the FFI functions you you use a DSL that is similar to C declarations. Often you can copy paste function prototypes from ".h" files with very minimal modifications. With ctypes you need to specify the types with Python function calls. See "ffi.cdef": https://luajit.org/ext_ffi.html https://luajit.org/ext_ffi.html 2) Performance. If your code is inside a JIT-compiled trace, LuaJIT FFI calls have minimal overhead. They compile down to something very similar to what a C compiler would generate. Ctypes, on the other hand, must "interpret" the FFI calls which adds more runtime overhead (although admittedly this is also true for LuaJIT if your code ends up outside a compiled trace).