Is it that easy?
I searched for an ebuild of couchapp and didn’t find anything that way. So I looked for some examples of python ebuilds and stumbled upon http://gentoo-overlays.zugaina.org/dberkholz/index.html.en. There I looked in some random packages and made a first draft.
# Distributed under the terms of the GNU General Public License v2
# $Header: $
inherit distutils
DESCRIPTION="Couchapp makes standalone CouchDB application development easy"
HOMEPAGE="http://github.com/couchapp/couchapp"
SRC_URI="http://github.com/downloads/couchapp/couchapp/Couchapp-${PV}.tar.gz"
LICENSE="Apache"
KEYWORDS="~amd64"
SLOT="0"
IUSE=""
DEPEND="dev-python/setuptools"
And it worked! No need to read the Gentoo Development Guide.
Thank’s Gentoo.
Update: Now in a layman overlay at http://github.com/ndt/ogo-ndt