Before installing CL-GTK2, install its dependencies. CL-GTK2 has the following dependencies (note that versions are required; CL-GTK2 uses features that became available in these versions and would not work with older versions):

1. CFFI (version >= 0.10.4)
2. Trivial-Garbage (version >= 0.18)
3. Iterate (version >= 1.4.3)
4. Bordeaux-Threads (version >= 0.6.0)
5. Closer-MOP (version >= 0.55)
6. cl-opengl (if you intend to use cl-gtk2-gtkglext)
7. cl-cairo2 (if you intend to use cl-gtk2-cairo)

CL-GTK2 requires Gtk+ version >= 2.16.

At first, source code should be downloaded. Current version of CL-GTK2 can be downloaded from http://common-lisp.net/project/cl-gtk2/files/cl-gtk2-0.1.1.tar.gz.

Development tree of CL-GTK2 can be cloned with Git:

git clone git://repo.or.cz/cl-gtk2.git

or, using the mirror:

git clone git://github.com/dmitryvk/cl-gtk2.git

To install CL-GTK2, unpack the CL-GTK2 sources, and add them to asdf:*central-registry*:

(push "/path/to/cl-gtk2/glib/" asdf:*central-registry*)
(push "/path/to/cl-gtk2/pango/" asdf:*central-registry*)
(push "/path/to/cl-gtk2/gdk/" asdf:*central-registry*)
(push "/path/to/cl-gtk2/gtk/" asdf:*central-registry*)
(push "/path/to/cl-gtk2/gtk-glext/" asdf:*central-registry*)
(push "/path/to/cl-gtk2/cairo/" asdf:*central-registry*)

or create symlinks:

cd ~/.sbcl/systems      # or other directory in asdf:*central-registry*
ln -s /path/to/cl-gtk2/glib/cl-gtk2-glib.asd .
ln -s /path/to/cl-gtk2/pango/cl-gtk2-pango.asd .
ln -s /path/to/cl-gtk2/gdk/cl-gtk2-gdk.asd .
ln -s /path/to/cl-gtk2/gtk/cl-gtk2-gtk.asd .
ln -s /path/to/cl-gtk2/gtkglext/cl-gtk2-gtkglext.asd .
ln -s /path/to/cl-gtk2/cairo/cl-gtk2-cairo.asd .

In Gentoo Linux, it is possible to use layman (see Gentoo Overlays Users' Guide) to add lisp and cl-gtk2 overlays that contains neccessary ebuilds:

layman -a lisp
layman --overlays=http://github.com/dmitryvk/cl-gtk2-overlay/raw/master/layman-list.xml -a cl-gtk2
emerge cl-gtk2