common-lisp λgtk is a cross-platform Lisp interface to the complete GTK+2 family of shared libraries. λgtk provides Lisp programmers with the following set of features: * Portable GUI programming across the supported Lisp environments. * Automatic conversion between Lisp data (booleans, numbers, strings) and their equivalent GTK types. * Lisp names for GTK's enums, structs and functions. * Lisp accessor functions to read/write slot values in GTK structs. * Lisp symbol package(s) that export the GTK API and a read time conditional #+:gtk in *features*. * A small set of utilities for working with GTK pointers, callbacks and foreign storage in a portable way.