This page describes how to write lisp codes in C within Librep. It's far from complete. Functions and data types are registered on modules load. The dealing with registered data types is handled by call-backs. Librep uses a mark and sweep garbage collector. For each data type registered, appropriate mark and sweep functions are registered. Most of macros in this page are defined in librep/src/rep_lisp.h and sawfish/src/sawfish.h.