Get the latest version from the google project page.
$ mkdir couchdb
$ cd couchdb
$ repo init -u git://github.com/couchbase/couchdb-manifest.git
$ repo sync
or, for the new and exciting preview branch:
$ mkdir couchdb
$ cd couchdb
$ repo init -u git://github.com/couchbase/couchdb-manifest.git -m branch-preview.xml
$ repo sync
$ rake