Climacs attempts to improve on the concepts found in other free Common Lisp-based emacsen, such as Goatee (the original editor component of McCLIM) or Portable Hemlock. Many design choices of Climacs are based more on the editor of the Genera operating system, Zmacs, and the other original Lisp emacsen, such as Hemlock, than on GNU Emacs. Climacs is free software, released under the LGPL (version 2 or, at your option, any later version).